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PHP Basic Algorithm: Exercises, Practice, Solution

PHP Basic Algorithm [136 exercises with solution]

[An editor is available at the bottom of the page to write and execute the scripts.]

1. Write a PHP program to compute the sum of the two given integer values. If the two values are the same, then returns triple their sum. Go to the editor
Sample Input
1, 2
3, 2
2, 2
Sample Output:
3
5
12
Click me to see the sample solution

2. Write a PHP program to get the absolute difference between n and 51. If n is greater than 51 return triple the absolute difference. Go to the editor
Sample Input:
53
30
51
Sample Output:
6
21
0
Click me to see the sample solution

3. Write a PHP program to check two given integers, and return true if one of them is 30 or if their sum is 30. Go to the editor
Sample Input:
30, 0
25, 5
20, 30
20, 25
Sample Output:
bool(true)
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

4. Write a PHP program to check a given integer and return true if it is within 10 of 100 or 200. Go to the editor
Sample Input:
103
90
89
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

5. Write a PHP program to create a new string where 'if' is added to the front of a given string. If the string already begins with 'if', return the string unchanged. Go to the editor
Sample Input:
"if else"
"else"
Sample Output:
if else
if else
Click me to see the sample solution

6. Write a PHP program to remove the character in a given position of a given string. The given position will be in the range 0..string length -1 inclusive. Go to the editor
Sample Input:
"Python", 1
"Python", o
"Python", 4
Sample Output:
Pthon
ython
Pythn
Click me to see the sample solution

7. Write a PHP program to exchange the first and last characters in a given string and return the new string. Go to the editor
Sample Input:
"abcd"
"a"
"xy"
Sample output:
dbca
a
yx
Click me to see the sample solution

8. Write a PHP program to create a new string which is 4 copies of the 2 front characters of a given string. If the given string length is less than 2 return the original string. Go to the editor
Sample Input:
"C Sharp"
"JS"
"a"
Sample Output:
C C C C
JSJSJSJS
a
Click me to see the sample solution

9. Write a PHP program to create a new string with the last char added at the front and back of a given string of length 1 or more. Go to the editor
Sample Input:
"Red"
"Green"
"1"
Sample Output:
dRedd
nGreenn
111
Click me to see the sample solution

10. Write a PHP program to check if a given positive number is a multiple of 3 or a multiple of 7. Go to the editor
Sample Input
3
14
12
37
Sample Output:
bool(true)
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

11. Write a PHP program to create a new string taking the first 3 characters of a given string and return the string with the 3 characters added at both the front and back. If the given string length is less than 3, use whatever characters are there. Go to the editor
Sample Input:
"Python"
"JS"
"Code"
Sample Output:
PytPythonPyt
JSJSJS
CodCodeCod
Click me to see the sample solution

12. Write a PHP program to check if a given string starts with 'C#' or not. Go to the editor
Sample Input:
"PHP"
"C#"
"C++"
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

13. Write a PHP program to check if one given temperatures is less than 0 and the other is greater than 100. Go to the editor
Sample Input:
120, -1
-1, 120
2, 120
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

14. Write a PHP program to check two given integers whether either of them is in the range 100..200 inclusive. Go to the editor
Sample Input:
100, 199
250, 300
105, 190
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution

15. Write a PHP program to check whether three given integer values are in the range 20..50 inclusive. Return true if 1 or more of them are in the said range otherwise false. Go to the editor
Sample Input:
11, 20, 12
30, 30, 17
25, 35, 50
15, 12, 8
Sample Output:
bool(true)
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

16. Write a PHP program to check whether two given integer values are in the range 20..50 inclusive. Return true if 1 or other is in the said range otherwise false. Go to the editor
Sample Input:
20, 84
14, 50
11, 45
25, 40
Sample Output:
bool(true)
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

17. Write a PHP program to check if a string 'yt' appears at index 1 in a given string. If it appears return a string without 'yt' otherwise return the original string. Go to the editor
Sample Input:
"Python"
"ytade"
"jsues"
Sample Output:
Phon
ytade
jsues
Click me to see the sample solution

18. Write a PHP program to check the largest number among three given integers. Go to the editor
Sample Input:
1,2,3
1,3,2
1,1,1
1,2,2
Sample Output:
3
3
1
2
Click me to see the sample solution

19. Write a PHP program to check which number nearest to the value 100 among two given integers. Return 0 if the two numbers are equal. Go to the editor
Sample Input:
78, 95
95, 95
99, 70
Sample Output:
95
0
99
Click me to see the sample solution

20. Write a PHP program to check whether two given integers are in the range 40..50 inclusive, or they are both in the range 50..60 inclusive. Go to the editor
Sample Input:
78, 95
25, 35
40, 50
55, 60
Sample Output:
bool(false)
bool(false)
bool(true)
bool(true)
Click me to see the sample solution

21. Write a PHP program to find the larger value from two positive integer values that is in the range 20..30 inclusive, or return 0 if neither is in that range. Go to the editor
Sample Input:
78, 95
20, 30
21, 25
28, 28
Sample Output:
0
30
25
28
Click me to see the sample solution

22. Write a PHP program to check if a given string contains between 2 and 4 'z' character. Go to the editor
Sample Input:
"frizz"
"zane"
"Zazz"
"false"
Sample Output:
bool(true)
bool(false)
bool(true)
bool(false)
Click me to see the sample solution

23. Write a PHP program to check if two given non-negative integers have the same last digit. Go to the editor
Sample Input:
123, 456
12, 512
7, 87
12, 45
Sample Output:
bool(false)
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

24. Write a PHP program to convert the last 3 characters of a given string in upper case. If the length of the string has less than 3 then uppercase all the characters. Go to the editor
Sample Input:
"Python"
"Javascript"
"js"
"PHP"
Sample Output:
PytHON
JavascrIPT
JS
PHP
Click me to see the sample solution

25. Write a PHP program to create a new string which is n (non-negative integer) copies of a given string. Go to the editor
Sample Input:
"JS", 2
"JS", 3
"JS", 1
Sample Output:
JSJS
JSJSJS
JS
Click me to see the sample solution

26. Write a PHP program to create a new string which is n (non-negative integer) copies of the the first 3 characters of a given string. If the length of the given string is less than 3 then return n copies of the string. Go to the editor
Sample Input:
"Python", 2
"Python", 3
"JS", 3
Sample Output:
PytPyt
PytPytPyt
JSJSJS
Click me to see the sample solution

27. Write a PHP program to count the string "aa" in a given string and assume "aaa" contains two "aa". Go to the editor
Sample Input:
"bbaaccaag"
"jjkiaaasew"
"JSaaakoiaa"
Sample Output:
2
2
3
Click me to see the sample solution

28. Write a PHP program to check if the first appearance of "a" in a given string is immediately followed by another "a". Go to the editor
Sample Input:
"caabb"
"babaaba"
"aaaaa"
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution

29. Write a PHP program to create a new string made of every other character starting with the first from a given string. Go to the editor
Sample Input:
"Python"
"PHP"
"JS"
Sample Output:
Pto
PP
J
Click me to see the sample solution

30. Write a PHP program to create a string like "aababcabcd" from a given string "abcd". Go to the editor
Sample Input:
"abcd"
"abc"
"a"
Sample Output:
aababcabcd
aababc
a
Click me to see the sample solution

31. Write a PHP program to count a substring of length 2 appears in a given string and also as the last 2 characters of the string. Do not count the end substring. Go to the editor
Sample Input:
"abcdsab"
"abcdabab"
"abcabdabab"
"abcabd"
Sample Output:
1
2
3
0
Click me to see the sample solution

32. Write a PHP program to check a specified number is present in a given array of integers. Go to the editor
Sample Input:
{1,2,9,3}, 3
{1,2,2,3}, 2
{1,2,2,3}, 9
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

33. Write a PHP program to check if one of the first 4 elements in an array of integers is equal to a given element. Go to the editor
Sample Input:
{1,2,9,3}, 3
{1,2,3,4,5,6}, 2
{1,2,2,3}, 9
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

34. Write a PHP program to check whether the sequence of numbers 1, 2, 3 appears in a given array of integers somewhere. Go to the editor
Sample Input:
{1,1,2,3,1}
{1,1,2,4,1}
{1,1,2,1,2,3}
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution

35. Write a PHP program to compare two given strings and return the number of the positions where they contain the same length 2 substring. Go to the editor
Sample Input:
"abcdefgh", "abijsklm"
"abcde", "osuefrcd"
"pqrstuvwx", "pqkdiewx"
Sample Output:
1
1
2
Click me to see the sample solution

36. Write a PHP program to create a new string of the characters at indexes 0,1,4,5,8,9 ... from a given string. Go to the editor
Sample Input:
"Python"
"JavaScript"
"HTML"
Sample Output:
Pyon
JaScpt
HT
Click me to see the sample solution

37. Write a PHP program to count the number of two 5's are next to each other in an array of integers. Also count the situation where the second 5 is actually a 6. Go to the editor
Sample Input:
{ 5, 5, 2 }
{ 5, 5, 2, 5, 5 }
{ 5, 6, 2, 9}
Sample Output:
1
2
1
Click me to see the sample solution

38. Write a PHP program to check if a triple is presents in an array of integers or not. If a value appears three times in a row in an array it is called a triple. Go to the editor
Sample Input:
{ 1, 1, 2, 2, 1 }
{ 1, 1, 2, 1, 2, 3 }
{ 1, 1, 1, 2, 2, 2, 1 }
Sample Output:
bool(false)
bool(false)
bool(true)
Click me to see the sample solution

39. Write a PHP program to compute the sum of the two given integers. If the sum is in the range 10..20 inclusive return 30. Go to the editor
Sample Input:
12, 17
2, 17
22, 17
20, 0
Sample Output:
29
30
39
30
Click me to see the sample solution

40. Write a PHP program that accept two integers and return true if either one is 5 or their sum or difference is 5. Go to the editor
Sample Input:
5, 4
4, 3
1, 4
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution

41. Write a PHP program to test if a given non-negative number is a multiple of 13 or it is one more than a multiple of 13. Go to the editor
Sample Input:
13
14
27
41
Sample Output:
bool(true)
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

42. Write a PHP program to check if a given non-negative given number is a multiple of 3 or 7, but not both. Go to the editor
Sample Input:
3
7
21
Sample Output:
int(1)
int(1)
int(0)
Click me to see the sample solution

43. Write a PHP program to check if a given number is within 2 of a multiple of 10. Go to the editor
Sample Input:
3
7
8
21
Sample Output:
bool(false)
bool(false)
bool(true)
bool(true)
Click me to see the sample solution

44. Write a PHP program to compute the sum of the two given integers. If one of the given integer value is in the range 10..20 inclusive return 18. Go to the editor
Sample Input:
3, 7
10, 11
10, 20
21, 220
Sample Output:
10
18
18
241
Click me to see the sample solution

45. Write a PHP program to check whether a given string starts with "F" or ends with "B". If the string starts with "F" return "Fizz" and return "Buzz" if it ends with "B" If the string starts with "F" and ends with "B" return "FizzBuzz". In other cases return the original string. Go to the editor
Sample Input:
"FizzBuzz"
"Fizz"
"Buzz"
"Founder"
Sample Output:
Fizz
Fizz
Buzz
Fizz
Click me to see the sample solution

46. Write a PHP program to check if it is possible to add two integers to get the third integer from three given integers. Go to the editor
Sample Input:
1, 2, 3
4, 5, 6
-1, 1, 0
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution

47. Write a PHP program to check if y is greater than x, and z is greater than y from three given integers x,y,z. Go to the editor
Sample Input:
1, 2, 3
4, 5, 6
-1, 1, 0
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

48. Write a PHP program to check if three given numbers are in strict increasing order, such as 4 7 15, or 45, 56, 67, but not 4 ,5, 8 or 6, 6, 8.However,if a fourth parameter is true, equality is allowed, such as 6, 6, 8 or 7, 7, 7. Go to the editor
Sample Input:
1, 2, 3, false
1, 2, 3, true
10, 2, 30, false
10, 10, 30, true
Sample Output:
bool(true)
bool(true)
bool(false)
bool(true)
Click me to see the sample solution

49. Write a PHP program to check if two or more non-negative given integers have the same rightmost digit. Go to the editor
Sample Input:
11, 21, 31
11, 22, 31
11, 22, 33
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

50. Write a PHP program to check three given integers and return true if one of them is 20 or more less than one of the others. Go to the editor
Sample Input:
11, 21, 31
11, 22, 31
10, 20, 15
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

51. Write a PHP program to find the larger from two given integers. However if the two integers have the same remainder when divided by 7, then the return the smaller integer. If the two integers are the same, return 0. Go to the editor
Sample Input:
11, 21
11, 20
10, 10
Sample Output:
21
20
0
Click me to see the sample solution

52. Write a PHP program to check two given integers, each in the range 10..99. Return true if a digit appears in both numbers, such as the 3 in 13 and 33. Go to the editor
Sample Input:
11, 21
11, 20
10, 10
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution

53. Write a PHP program to compute the sum of two given non-negative integers x and y as long as the sum has the same number of digits as x. If the sum has more digits than x then return x without y. Go to the editor
Sample Input:
4, 5
7, 4
10, 10
Sample Output:
9
7
20
Click me to see the sample solution

54. Write a PHP program to compute the sum of three given integers. If the two values are same return the third value. Go to the editor
Sample Input:
4, 5, 7
7, 4, 12
10, 10, 12
12, 12, 18
Sample Output:
16
23
12
18
Click me to see the sample solution

55. Write a PHP program to compute the sum of the three integers. If one of the values is 13 then do not count it and its right towards the sum. Go to the editor
Sample Input:
4, 5, 7
7, 4, 12
10, 13, 12
13, 12, 18
Sample Output:
16
23
10
0
Click me to see the sample solution

56. Write a PHP program to compute the sum of the three given integers. However, if any of the values is in the range 10..20 inclusive then that value counts as 0, except 13 and 17. Go to the editor
Sample Input:
4, 5, 7
7, 4, 12
10, 13, 12
17, 12, 18
Sample Output:
16
11
13
17
Click me to see the sample solution

57. Write a PHP program to check two given integers and return the value whichever value is nearest to 13 without going over. Return 0 if both numbers go over. Go to the editor
Sample Input:
4, 5
7, 12
10, 13
17, 33
Sample Output:
5
12
13
0
Click me to see the sample solution

58. Write a PHP program to check three given integers (small, medium and large) and return true if the difference between small and medium and the difference between medium and large is same. Go to the editor
Sample Input:
4, 5, 6
7, 12, 13
-1, 0, 1
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution

59. Write a PHP program to create a new string using two given strings s1, s2, the format of the new string will be s1s2s2s1. Go to the editor
Sample Input:
"Hi", "Hello"
"whats", "app"
Sample Output:
HiHelloHelloHi
whatsappappwhats
Click me to see the sample solution

60. Write a PHP program to insert a given string into middle of the another given string of length 4. Go to the editor
Sample Input:
"[[]]","Hello"
"(())", "Hi"
Sample Output:
[[Hello]]
((Hi))
Click me to see the sample solution

61. Write a PHP program to create a new string using three copies of the last two character of a given string of length atleast two. Go to the editor
Sample Input:
"Hello"
"Hi"
Sample Output:
lololo
HiHiHi
Click me to see the sample solution

62. Write a PHP program to create a new string using first two characters of a given string. If the string length is less than 2 then return the original string. Go to the editor
Sample Input:
"Hello"
"Hi"
"H"
" "
Sample Output:
Hello
Hi
H
Click me to see the sample solution

63. Write a PHP program to create a new string of the first half of a given string of even length. Go to the editor
Sample Input:
"Hello"
"Hi"
Sample Output:
He
H
Click me to see the sample solution

64. Write a PHP program to create a new string without the first and last character of a given string of length atleast two. Go to the editor
Sample Input:
"Hello"
"Hi"
"Python"
Sample Output:
ell

ytho
Click me to see the sample solution

65. Write a PHP program to create a new string from two given string one is shorter and another is longer. The format of the new string will be long string + short string + long string. Go to the editor
Sample Input:
"Hello", "Hi"
"JS", "Python"
Sample Output:
HelloHiHello
PythonJSPython
Click me to see the sample solution

66. Write a PHP program to concat two given string of length atleast 1, after removing their first character. Go to the editor
Sample Input:
"Hello", "Hi"
"JS", "Python"
Sample Output:
elloi
Sython
Click me to see the sample solution

67. Write a PHP program to move the first two characters to the end of a given string of length at least two. Go to the editor
Sample Input:
"Hello"
"JS"
Sample Output:
lloHe
JS
Click me to see the sample solution

68. Write a PHP program to move the last two characters to the start of a given string of length at least two. Go to the editor
Sample Input:
"Hello"
"JS"
Sample Output:
loHel
JS
Click me to see the sample solution

69. Write a PHP program to create a new string without the first and last character of a given string of any length. Go to the editor
Sample Input:
"Hello"
"JS"
''
Sample Output:
ell
Click me to see the sample solution

70. Write a PHP program to create a new string using the two middle characters of a given string of even length (at least 2). Go to the editor
Sample Input:
"Hell"
"JS"
Sample Output:
el
JS
Click me to see the sample solution

71. Write a PHP program to check if a given string ends with "on". Go to the editor
Sample Input:
"Hello"
"Python"
"on"
"o"
Sample Output:
string(2) "lo"
string(2) "on"
string(2) "on"
string(1) "o"
Click me to see the sample solution

72. Write a PHP program to create a new string using the first and last n characters from a given string of length at least n. Go to the editor
Sample Input:
"Hello", 1
"Python", 2
"on", 1
"o", 1
Sample Output:
Ho
Pyon
on
oo
Click me to see the sample solution

73. Write a PHP program to create a new string of length 2 starting at the given index of a given string. Go to the editor
Sample Input:
"Hello", 1
"Python", 2
"on", 1
Sample Output:
el
th
on
Click me to see the sample solution

74. Write a PHP program to create a new string taking 3 characters from the middle of a given string at least 3. Go to the editor
Sample Input:
"Hello"
"Python"
"abc"
Sample Output:
ell
yth
abc
Click me to see the sample solution

75. Write a PHP program to create a new string of length 2, using first two characters of a given string. If the given string length is less than 2 use '#' as missing characters. Go to the editor
Sample Input:
"Hello"
"Python"
"a"
""
Sample Output:
He
Py
a#
#
Click me to see the sample solution

76. Write a PHP program to create a new string taking the first character from a given string and the last character from another given string. If the length of any given string is 0, use '#' as its missing character. Go to the editor
Sample Input:
"Hello", "Hi"
"Python", "PHP"
"JS", "JS"
"Csharp", ""
Sample Output:
Hi
PP
JS
C#
Click me to see the sample solution

77. Write a PHP program to concat two given strings (lowercase). If there are any double character in new string then omit one character. Go to the editor
Sample Input:
"abc", "cat"
"python", "php"
"php", "php"
Sample Output:
abccat
PythonPHP
phpp
Click me to see the sample solution

78. Write a PHP program to create a new string from a given string after swapping last two characters. Go to the editor
Sample Input:
"Hello"
"Python"
"PHP"
"JS"
"C"
Sample Output:
Helol
Pythno
PPH
SJ
C
Click me to see the sample solution

79. Write a PHP program to check if a given string begins with 'abc' or 'xyz'. If the string begins with 'abc' or 'xyz' return 'abc' or 'xyz' otherwise return the empty string. Go to the editor
Sample Input:
"abc"
"abcdef"
"C"
"xyz"
"xyzsder"
Sample Output:
abc
abc

xyz
xyz
Click me to see the sample solution

80. Write a PHP program to check whether the first two characters and last two characters of a given string are same. Go to the editor
Sample Input:
"abab"
"abcdef"
"xyzsderxy"
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution

81. Write a PHP program to concat two given strings. If the given strings have different length remove the characters from the longer string. Go to the editor
Sample Input:
"abc", "abcd"
"Python", "Python"
"JS", "Python"
Sample Output:
abcbcd
PythonPython
JSon
Click me to see the sample solution

82. Write a PHP program to create a new string using 3 copies of the first 2 characters of a given string. If the length of the given string is less than 2 use the whole string. Go to the editor
Sample Input:
"abc"
"Python"
"J"
Sample Output:
ababab
PyPyPy
JJJ
Click me to see the sample solution

83. Write a PHP program to create a new string from a given string. If the two characters of the given string from its beginning and end are same return the given string without the first two characters otherwise return the original string. Go to the editor
Sample Input:
"abcab"
"Python"
Sample Output:
cab
Python
Click me to see the sample solution

84. Write a PHP program to create a new string from a given string without the first and last character if the first or last characters are 'a' otherwise return the original given string. Go to the editor
Sample Input:
"abcab"
"python"
"abcda"
"jython"
Sample Output:
bcab
Python
bcd
jython
Click me to see the sample solution

85. Write a PHP program to create a new string from a given string. If the first or first two characters is 'a', return the string without those 'a' characters otherwise return the original given string. Go to the editor
Sample Input:
"abcab"
"python"
"aacda"
"jython"
Sample Output:
bcab
Python
cda
jython
Click me to see the sample solution

86. Write a PHP program to check a given array of integers of length 1 or more and return true if 10 appears as either first or last element in the given array. Go to the editor
Sample Input:
{ 10, 20, 40, 50 }
{ 5, 20, 40, 10 }
{ 10, 20, 40, 10 }
{ 12, 24, 35, 55 }
Sample Output:
bool(true)
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

87. Write a PHP program to check a given array of integers of length 1 or more and return true if the first element and the last element are equal in the given array. Go to the editor
Sample Input:
{ 10, 20, 40, 50 }
{ 10, 20, 40, 10 }
{ 12, 24, 35, 55 }
Sample Output:
bool(false)
bool(true)
bool(false)
Click me to see the sample solution

88. Write a PHP program to check two given arrays of integers of length 1 or more and return true if they have the same first element or they have the same last element. Go to the editor
Sample Input:
{[10, 20, 40, 50], [10, 20, 40, 50]}
{[10, 20, 40, 10], [10, 20, 40, 5]}
{[12, 24, 35, 55], [1, 20, 40, 5]}
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

89. Write a PHP program to compute the sum of the elements of an given array of integers. Go to the editor
Sample Input:
{ 10, 20, 30, 40, 50 }
{ 10, 20, -30, -40, 50 }
Sample Output:
150
10
Click me to see the sample solution

90. Write a PHP program to rotate the elements of a given array of integers (length 4 ) in left direction and return the new array. Go to the editor
Sample Input:
{ 10, 20, -30, -40 }
Sample Output:
Rotated array: 20,-30,-40,10
Click me to see the sample solution

91. Write a PHP program to reverse a given array of integers and length 5. Go to the editor
Sample Input:
{ 10, 20, -30, -40, 50 }
Sample Output:
Reverse array: 50,-40,-30,20,10
Click me to see the sample solution

92. Write a PHP program to find out the maximum element between the first or last element in a given array of integers ( length 4), replace all elements with maximum element. Go to the editor
Sample Input:
{ 10, 20, -30, -40 }
Sample Output:
New array with maximum values: 20,20,20,20
Click me to see the sample solution

93. Write a PHP program to create a new array containing the middle elements from the two given arrays of integers, each length 5. Go to the editor
Sample Input:
{ 10, 20, -30, -40, 30 }, { 10, 20, 30, 40, 30 }
Sample Output:
New array: -30, 30
Click me to see the sample solution

94. Write a PHP program to create a new array taking the first and last elements of a given array of integers and length 1 or more. Go to the editor
Sample Input:
{ 10, 20, -30, -40, 30 }
Sample Output:
New array: 10,30
Click me to see the sample solution

95. Write a PHP program to check if a given array of integers and length 2, contains 15 or 20. Go to the editor
Sample Input:
{ 12, 20 }
{ 14, 15 }
{ 11, 21 }
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

96. Write a PHP program to check if a given array of integers and length 2, does not contain 15 or 20. Go to the editor
Sample Input:
{ 12, 20 }
{ 14, 15 }
{ 11, 21 }
Sample Output:
bool(false)
bool(false)
bool(true)
Click me to see the sample solution

97. Write a PHP program to check a given array of integers and return true if the array contains 10 or 20 twice. The length of the array will be 0, 1, or 2. Go to the editor
Sample Input:
{ 12, 20 }
{ 20, 20 }
{ 10, 10 }
{ 10 }
Sample Output:
bool(false)
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

98. Write a PHP program to check a given array of integers, length 3 and create a new array. If there is a 5 in the given array immediately followed by a 7 then set 7 to 1. Go to the editor
Sample Input:
{ 1, 5, 7 }
Sample Output:
New array with maximum values: 1,5,1
Click me to see the sample solution

99. Write a PHP program to compute the sum of the two given arrays of integers, length 3 and find the array which has the largest sum. Go to the editor
Sample Input:
{ 10, 20, -30 }, { 10, 20, 30 }
Sample Output:
New array with maximum values: 10,20,30
Click me to see the sample solution

100. Write a PHP program to create an array taking two middle elements from a given array of integers of length even. Go to the editor
Sample Input:
{ 1, 5, 7, 9, 11, 13 }
Sample Output:
New array: 7 9
Click me to see the sample solution

101. Write a PHP program to create a new array from two give array of integers, each length 3. Go to the editor
Sample Input:
{ 10, 20, 30 }, { 40, 50, 60 }
Sample Output:
New array: 10,20,30,40,50,60
Click me to see the sample solution

102. Write a PHP program to create a new array swapping the first and last elements of a given array of integers and length will be least 1. Go to the editor
Sample Input:
{ 1, 5, 7, 9, 11, 13 }
Sample Output:
New array, after swapping first and last elements: 13,5,7,9,11,1
Click me to see the sample solution

103. Write a PHP program to create a new array length 3 from a given array (length atleast 3) using the elements from the middle of the array. Go to the editor
Sample Input:
{ 1, 5, 7, 9, 11, 13 }
Sample Output:
New array: 7,9,11
Click me to see the sample solution

104. Write a PHP program to find the largest value from first, last, and middle elements of a given array of integers of odd length (atleast 1). Go to the editor
Sample Input:
{1}
{1,2,9}
{1,2,9,3,3}
{1,2,3,4,5,6,7}
{1,2,2,3,7,8,9,10,6,5,4}
Sample Output:
1
9
9
7
8
Click me to see the sample solution

105. Write a PHP program to create a new array taking the first two elements from a given array. If the length of the given array is less than 2 then return the give array. Go to the editor
Sample Input:
{ 1, 5, 7, 9, 11, 13 }
Sample Output:
New array: 1,5
Click me to see the sample solution

106. Write a PHP program to count even number of elements in a given array of integers. Go to the editor
Sample Input:
{ 1, 5, 7, 9, 10, 12 }
Sample Output:
Number of even elements: 2
Click me to see the sample solution

107. Write a PHP program to compute the difference between the largest and smallest values in a given array of integers and length one or more. Go to the editor
Sample Input:
{ 1, 5, 7, 9, 10, 12 }
Sample Output:
Difference between the largest and smallest values: 11
Click me to see the sample solution

108. Write a PHP program to compute the sum of values in a given array of integers except the number 17. Return 0 if the given array has no integer. Go to the editor
Sample Input:
{ 1, 5, 7, 9, 10, 17 }
Sample Output:
Sum of values in the array of integers except the number 17: 32
Click me to see the sample solution

109. Write a PHP program to compute the sum of the numbers in a given array except those numbers starting with 5 followed by atleast one 6. Return 0 if the given array has no integer. Go to the editor
Sample Input:
{ 1, 5, 7, 9, 10, 17 }
Sample Output:
Sum of the numbers of the said array except those numbers starting with 5 followed by atleast one 6:
1
Click me to see the sample solution

110. Write a PHP program to check if a given array of integers contains 5 next to a 5 somewhere. Go to the editor
Sample Input:
{ 1, 5, 6, 9, 10, 17 }
{ 1, 5, 5, 9, 10, 17 }
{ 1, 5, 5, 9, 10, 17, 5, 5 }
Sample Output:
bool(false)
bool(true)
bool(true)
Click me to see the sample solution

111. Write a PHP program to check whether a given array of integers contains 5's and 7's. Go to the editor
Sample Input:
{ 1, 5, 6, 9, 10, 17 }
{ 1, 4, 7, 9, 10, 17 }
{ 1, 1, 2, 9, 10, 17}
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

112. Write a PHP program to check if the sum of all 5' in the array exactly 15 in a given array of integers. Go to the editor
Sample Input:
{ 1, 5, 6, 9, 10, 17 }
{ 1, 5, 5, 5, 10, 17 }
{ 1, 1, 5, 5, 5, 5}
Sample Output:
bool(false)
bool(true)
bool(false)
Click me to see the sample solution

113. Write a PHP program to check if the number of 3's is greater than the number of 5's. Go to the editor
Sample Input:
{ 1, 5, 6, 9, 3, 3 }
{ 1, 5, 5, 5, 10, 17 }
{ 1, 3, 3, 5, 5, 5}
Sample Output:
bool(true)
bool(false)
bool(false)
Click me to see the sample solution

114. Write a PHP program to check if a given array of integers contains a 3 or a 5. Go to the editor
Sample Input:
{ 5, 5, 5, 5, 5 }
{ 3, 3, 3, 3 }
{ 3, 3, 3, 5, 5, 5}
{ 1, 6, 8, 10}
Sample Output:
bool(true)
bool(true)
bool(true)
bool(false)
Click me to see the sample solution

115. Write a PHP program to check if a given array of integers contains no 3 or a 5. Go to the editor
Sample Input:
{ 5, 5, 5, 5, 5 }
{ 3, 3, 3, 3 }
{ 3, 3, 3, 5, 5, 5}
{ 1, 6, 8, 10}
Sample Output:
bool(true)
bool(true)
bool(false)
bool(true)
Click me to see the sample solution

116. Write a PHP program to check if an array of integers contains a 3 next to a 3 or a 5 next to a 5 or both. Go to the editor
Sample Input:
{ 5, 5, 5, 5, 5 }
{ 1, 2, 3, 4 }
{ 3, 3, 5, 5, 5, 5}
{ 1, 5, 5, 7, 8, 10}
Sample Output:
bool(true)
bool(false)
bool(true)
bool(true)
Click me to see the sample solution

117. Write a PHP program to check a given array of integers and return true if the given array contains two 5's next to each other, or two 5 separated by one element. Go to the editor
Sample Input:
{ 5, 5, 1, 5, 5 }
{ 1, 2, 3, 4 }
{ 3, 3, 5, 5, 5, 5}
{ 1, 5, 5, 7, 8, 10}
Sample Output:
bool(true)
bool(false)
bool(true)
bool(true)
Click me to see the sample solution

118. Write a PHP program to check a given array of integers and return true if there is a 3 with a 5 somewhere later in the given array. Go to the editor
Sample Input:
{ 3, 5, 1, 3, 7 }
{ 1, 2, 3, 4 }
{ 3, 3, 5, 5, 5, 5}
{ 2, 5, 5, 7, 8, 10}
Sample Output:
bool(true)
bool(false)
bool(true)
bool(false)
Click me to see the sample solution

119. Write a PHP program to check a given array of integers and return true if the given array contains either 2 even or 2 odd values all next to each other. Go to the editor
Sample Input:
{ 3, 5, 1, 3, 7 }
{ 1, 2, 3, 4 }
{ 3, 3, 5, 5, 5, 5}
{ 2, 4, 5, 6}
Sample Output:
bool(true)
bool(false)
bool(true)
bool(true)
Click me to see the sample solution

120. Write a PHP program to check a given array of integers and return true if the value 5 appears 5 times and there are no 5 next to each other. Go to the editor
Sample Input:
{ 3, 5, 1, 5, 3, 5, 7, 5, 1, 5 }
{ 3, 5, 5, 5, 5, 5, 5}
{ 3, 5, 2, 5, 4, 5, 7, 5, 8, 5}
{ 2, 4, 5, 5, 5, 5}
Sample Output:
bool(true)
bool(false)
bool(true)
bool(false)
Click me to see the sample solution

121. Write a PHP program to check a given array of integers and return true if every 5 that appears in the given array is next to another 5. Go to the editor
Sample Input:
{ 3, 5, 5, 3, 7 }
{ 3, 5, 5, 4, 1, 5, 7}
{ 3, 5, 5, 5, 5, 5}
{ 2, 4, 5, 5, 6, 7, 5}
Sample Output:
bool(true)
bool(false)
bool(true)
bool(false)
Click me to see the sample solution

122. Write a PHP program to check a given array of integers and return true if the specified number of same elements appears at the start and end of the given array. Go to the editor
Sample Input:
{ 3, 7, 5, 5, 3, 7 }, 2
{ 3, 7, 5, 5, 3, 7 }, 3
{ 3, 7, 5, 5, 3, 7, 5 }, 3
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution

123. Write a PHP program to check a given array of integers and return true if the array contains three increasing adjacent numbers. Go to the editor
Sample Input:
{ 1, 2, 3, 5, 3, 7 }
{ 3, 7, 5, 5, 3, 7 }
{ 3, 7, 5, 5, 6, 7, 5 }
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution

124. Write a PHP program to shift an element in left direction and return a new array. Go to the editor
Sample Input:
{ 10, 20, -30, -40, 50 }
Sample Output:
New array: 20,-30,-40,50,10
Click me to see the sample solution

125. Write a PHP program to create a new array taking the elements before the element value 5 from a given array of integers. Go to the editor
Sample Input:
{ 1, 2, 3, 5, 7 }
Sample Output:
New array: 1,2,3
Click me to see the sample solution

126. Write a PHP program to create a new array taking the elements after the element value 5 from a given array of integers. Go to the editor
Sample Input:
{ 1, 2, 3, 5, 7, 9, 11 }
Sample Output:
New array: 7,9,11
Click me to see the sample solution

127. Write a PHP program to create a new array from a given array of integers shifting all zeros to left direction. Go to the editor
Sample Input:
{ 1, 2, 0, 3, 5, 7, 0, 9, 11 }
Sample Output:
New array: 0,0,1,3,5,7,2,9,11
Click me to see the sample solution

128. Write a PHP program to create a new array after replacing all the values 5 with 0 shifting all zeros to right direction. Go to the editor
Sample Input:
{ 1, 2, 0, 3, 5, 7, 0, 9, 11 }
Sample Output:
New array: 1,2,3,7,9,11,0,0,0
Click me to see the sample solution

129. Write a PHP program to create new array from a given array of integers shifting all even numbers before all odd numbers. Go to the editor
Sample Input:
{ 1, 2, 5, 3, 5, 4, 6, 9, 11 }
Sample Output:
New array: 2,4,6,3,5,1,5,9,11
Click me to see the sample solution

130. Write a PHP program to check if the value of each element is equal or greater than the value of previous element of a given array of integers. Go to the editor
Sample Input:
{ 5, 5, 1, 5, 5 }
{ 1, 2, 3, 4 }
{ 3, 3, 5, 5, 5, 5}
{ 1, 5, 5, 7, 8, 10}
Sample Output:
bool(false)
bool(true)
bool(true)
bool(true)
Click me to see the sample solution

131. Write a PHP program to check a given array (length will be atleast 2) of integers and return true if there are two values 15, 15 next to each other. Go to the editor
Sample Input:
{ 5, 5, 1, 15, 15 }
{ 15, 2, 3, 4, 15 }
{ 3, 3, 15, 15, 5, 5}
{ 1, 5, 15, 7, 8, 15}
Sample Output:
bool(true)
bool(false)
bool(true)
bool(false)
Click me to see the sample solution

132. Write a PHP program to find the larger average value between the first and the second half of a given array of integers and minimum length is atleast 2. Assume that the second half begins at index (array length)/2. Go to the editor
Sample Input:
{ 1, 2, 3, 4, 6, 8 }
{ 15, 2, 3, 4, 15, 11 }
Sample Output:
6
10
Click me to see the sample solution

133. Write a PHP program to count the number of strings with given length in given array of strings. Go to the editor
Sample Input:
{"a", "b", "bb", "c", "ccc" }, 1
Sample Output:
Number of array:
3
Click me to see the sample solution

134. Write a PHP program to create a new array using the first n strings from a given array of strings. (n>=1 and <=length of the array). Go to the editor
Sample Input:
{"a", "b", "bb", "c", "ccc" }, 3
Sample Output:
a b bb
Click me to see the sample solution

135. Write a PHP program to check a positive integer and return true if it contains a number 2. Go to the editor
Sample Input:
123
13
222
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution

136. Write a PHP program to create a new array of given length using the odd numbers from a given array of positive integers. Go to the editor
Sample Input:
{1,2,3,5,7,9,10},3
Sample Output:
New array: 1,3,5
Click me to see the sample solution

PHP Code Editor:

More to Come !

Do not submit any solution of the above exercises at here, if you want to contribute go to the appropriate exercise page.



PHP: Tips of the Day

Get first key in a (possibly) associative array?

Starting from PHP 7.3, there is a new built in function called array_key_first() which will retrieve the first key from the given array without resetting the internal pointer. Check out the documentation for more info.

You can use reset and key:

reset($array);
$first_key = key($array);

It's essentially the same as your initial code, but with a little less overhead, and it's more obvious what is happening.

Just remember to call reset, or you may get any of the keys in the array. You can also use end instead of reset to get the last key.

If you wanted the key to get the first value, reset actually returns it:

$first_value = reset($array);

There is one special case to watch out for though (so check the length of the array first):

$arr1 = array(false);
$arr2 = array();
var_dump(reset($arr1) === reset($arr2)); // bool(true)

Ref : https://bit.ly/32ecxHN