# C Basic: Exercises, Practice, Solution

## C Basic Declarations and Expressions [52 exercises with solution]

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

1. Write a C program to print your name, date of birth. and mobile number. Go to the editor
Expected Output:

```Name   : Alexandra Abramov
DOB    : July 14, 1975
Mobile : 99-9999999999```

Click me to see the solution

2. Write a C program to print a block F using hash (#), where the F has a height of six characters and width of five and four characters. Go to the editor
Expected Output:

```######
#
#
#####
#
#
#```

Click me to see the solution

3. Write a C program to print a big 'C'. Go to the editor
Expected Output:

```    ######
##      ##
#
#
#
#
#
##      ##
######```

Click me to see the solution

4. Write a C program to print the following characters in a reverse way. Go to the editor
Test Characters: 'X', 'M', 'L'
Expected Output:
The reverse of XML is LMX
Click me to see the solution

5. Write a C program to compute the perimeter and area of a rectangle with a height of 7 inches. and width of 5 inches. Go to the editor
Expected Output:
Perimeter of the rectangle = 24 inches
Area of the rectangle = 35 square inches
Click me to see the solution

6. Write a C program to compute the perimeter and area of a circle with a radius of 6 inches. Go to the editor
Expected Output:
Perimeter of the Circle = 37.680000 inches
Area of the Circle = 113.040001 square inches
Click me to see the solution

7. Write a C program to display multiple variables. Go to the editor
Sample Variables :
a+ c, x + c,dx + x, ((int) dx) + ax, a + x, s + b, ax + b, s + c, ax + c, ax + ux
Declaration :
int a = 125, b = 12345;
long ax = 1234567890;
short s = 4043;
float x = 2.13459;
double dx = 1.1415927;
char c = 'W';
unsigned long ux = 2541567890;
Click me to see the solution

8. Write a C program to convert specified days into years, weeks and days. Go to the editor
Note: Ignore leap year.

Test Data :
Number of days : 1329
Expected Output :
Years: 3
Weeks: 33
Days: 3
Click me to see the solution

9. Write a C program that accepts two integers from the user and calculate the sum of the two integers. Go to the editor
Test Data :
Input the first integer: 25
Input the second integer: 38
Expected Output:
Sum of the above two integers = 63
Click me to see the solution

10. Write a C program that accepts two integers from the user and calculate the product of the two integers. Go to the editor
Test Data :
Input the first integer: 25
Input the second integer: 15
Expected Output:
Product of the above two integers = 375
Click me to see the solution

11. Write a C program that accepts two item’s weight (floating points' values ) and number of purchase (floating points' values) and calculate the average value of the items. Go to the editor
Test Data :
Weight - Item1: 15
No. of item1: 5
Weight - Item2: 25
No. of item2: 4
Expected Output:
Average Value = 19.444444
Click me to see the solution

12. Write a C program that accepts an employee's ID, total worked hours of a month and the amount he received per hour. Print the employee's ID and salary (with two decimal places) of a particular month. Go to the editor
Test Data :
Input the Employees ID(Max. 10 chars): 0342
Input the working hrs: 8
Salary amount/hr: 15000
Expected Output:
Employees ID = 0342
Salary = U\$ 120000.00
Click me to see the solution

13. Write a C program that accepts three integers and find the maximum of three. Go to the editor
Test Data :
Input the first integer: 25
Input the second integer: 35
Input the third integer: 15
Expected Output:
Maximum value of three integers: 35
Click me to see the solution

14. Write a C program to calculate a bike’s average consumption from the given total distance (integer value) traveled (in km) and spent fuel (in liters, float number – 2 decimal point). Go to the editor
Test Data :
Input total distance in km: 350
Input total fuel spent in liters: 5
Expected Output:
Average consumption (km/lt) 70.000
Click me to see the solution

15. Write a C program to calculate the distance between the two points. Go to the editor
Test Data :
Input x1: 25
Input y1: 15
Input x2: 35
Input y2: 10
Expected Output:
Distance between the said points: 11.1803
Click me to see the solution

16. Write a C program to read an amount (integer value) and break the amount into smallest possible number of bank notes. Go to the editor
Test Data :
Input the amount: 375
Expected Output:
There are:
3 Note(s) of 100.00
1 Note(s) of 50.00
1 Note(s) of 20.00
0 Note(s) of 10.00
1 Note(s) of 5.00
0 Note(s) of 2.00
0 Note(s) of 1.00
Click me to see the solution

17. Write a C program to convert a given integer (in seconds) to hours, minutes and seconds. Go to the editor
Test Data :
Input seconds: 25300
Expected Output:
There are:
H:M:S - 7:1:40
Click me to see the solution

18. Write a C program to convert a given integer (in days) to years, months and days, assumes that all months have 30 days and all years have 365 days. Go to the editor
Test Data :
Input no. of days: 2535
Expected Output:
6 Year(s)
11 Month(s)
15 Day(s)
Click me to see the solution

19. Write a C program that accepts 4 integers p, q, r, s from the user where r and s are positive and p is even. If q is greater than r and s is greater than p and if the sum of r and s is greater than the sum of p and q print "Correct values", otherwise print "Wrong values". Go to the editor
Test Data :
Input the second integer: 35
Input the third integer: 15
Input the fourth integer: 46
Expected Output:
Wrong values
Click me to see the solution

20. Write a C program to print the roots of Bhaskara’s formula from the given three floating numbers. Display a message if it is not possible to find the roots. Go to the editor
Test Data :
Input the first number(a): 25
Input the second number(b): 35
Input the third number(c): 12
Expected Output:
Root1 = -0.60000
Root2 = -0.80000
Click me to see the solution

21. Write a C program that reads an integer and check the specified range where it belongs. Print an error message if the number is negative and greater than 80. Go to the editor
Test Data :
Input an intger: 15
Expected Output:
Range [0, 20]
Click me to see the solution

22. Write a C program that read 5 numbers and sum of all odd values between them. Go to the editor
Test Data :
Input the first number: 11
Input the second number: 17
Input the third number: 13
Input the fourth number: 12
Input the fifth number: 5
Expected Output:
Sum of all odd values: 46
Click me to see the solution

22. Write a C program that reads three floating values and check if it is possible to make a triangle with them. Also calculate the perimeter of the triangle if the said values are valid. Go to the editor
Test Data :
Input the first integer: 5
Input the second integer: 15
Input the third integer: 10

Expected Output:
Numbers in sorted order: 5 10 15
Click me to see the solution

23. Write a C program that reads three floating values and check if it is possible to make a triangle with them. Also calculate the perimeter of the triangle if the said values are valid. Go to the editor
Test Data :
Input the first number: 25
Input the second number: 15
Input the third number: 35
Expected Output:
Perimeter = 75.0
Click me to see the solution

24. Write a C program that reads two integers and checks if they are multiplied or not. Go to the editor
Test Data :
Input the first number: 5
Input the second number: 15
Expected Output:
Multiplied!
Click me to see the solution

25. Write a C program that reads an integer between 1 and 12 and print the month of the year in English. Go to the editor
Test Data :
Input a number between 1 to 12 to get the month name: 8
Expected Output:
August
Click me to see the solution

26. Write a C program that prints all even numbers between 1 and 50 (inclusive). Go to the editor
Test Data :
Even numbers between 1 to 50 (inclusive):
Expected Output:
2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50
Click me to see the solution

27. Write a C program that read 5 numbers and counts the number of positive numbers and negative numbers. Go to the editor
Test Data :
Input the first number: 5
Input the second number: -4
Input the third number: 10
Input the fourth number: 15
Input the fifth number: -1
Expected Output:
Number of positive numbers: 3
Number of negative numbers: 2
Click me to see the solution

28. Write a C program that read 5 numbers and counts the number of positive numbers and print the average of all positive values. Go to the editor
Test Data :
Input the first number: 5
Input the second number: 8
Input the third number: 10
Input the fourth number: -5
Input the fifth number: 25
Expected Output:
Number of positive numbers: 4
Average value of the said positive numbers: 12.00
Click me to see the solution

29. Write a C program that read 5 numbers and sum of all odd values between them. Go to the editor
Test Data :
Input the first number: 5
Input the second number: 7
Input the third number: 9
Input the fourth number: 10
Input the fifth number: 13
Expected Output:
Sum of all odd values: 34
Click me to see the solution

30. Write a C program to find and print the square of each one of the even values from 1 to a specified value. Go to the editor
Test Data :
List of square of each one of the even values from 1 to a 4 :
Expected Output:
2^2 = 4
4^2 = 16
Click me to see the solution

31. Write a C program to check a given integer is positive even, negative even, positive odd or negative odd. Print even if the number is 0. Go to the editor
Test Data :
Input an integer: 13
Expected Output:
Positive Odd
Click me to see the solution

32. Write a C program to print all numbers between 1 to 100 which divided by a specified number and the remainder will be 3. Go to the editor
Test Data :
Input an integer: 25
Expected Output:
3
28
53
78
103
128
153
178
203
228
253
278
303
328
353
378
403
428
453
478
Click me to see the solution

33. Write a C program that accepts some integers from the user and find the highest value and the input position. Go to the editor
Test Data :
Input 5 integers:
5
7
15
23
45
Expected Output:
Highest value: 45
Position: 5
Click me to see the solution

34. Write a C program to print the numbers from the lowest to the highest (inclusive) and the sum of consecutive integers from a given pair of numbers. Go to the editor
Test Data :
Input a pair of numbers (for example 10,2):
Input first number of the pair: 10
Input second number of the pair: 2
Expected Output:
List of odd numbers: 3
5
7
9
Sum=24
Click me to see the solution

35. Write a C program to check if two numbers in a pair is in ascending order or descending order. Go to the editor
Test Data :
Input a pair of numbers (for example 10,2 : 2,10):
Input first number of the pair: 10
Expected Output:
Input second number of the pair: 2
The pair is in descending order!
Click me to see the solution

36. Write a C program to read a password until it is correct. For wrong password print "Incorrect password" and for correct password print "Correct password" and quit the program. The correct password is 1234. Go to the editor
Test Data :
Expected Output:
Click me to see the solution

Note: A Cartesian coordinate system is a coordinate system that specifies each point uniquely in a plane by a pair of numerical coordinates.
These are often numbered from 1st to 4th and denoted by Roman numerals: I (where the signs of the (x,y) coordinates are I(+,+), II (−,+), III (−,−), and IV (+,−).
Test Data :
Input the Coordinate(x,y):
x: 25
y: 15
Expected Output:
Click me to see the solution

38. Write a program that reads two numbers and divide the first number by second number. If the division not possible print "Division not possible". Go to the editor
Test Data :
Input two numbers:
x: 25
y: 5
Expected Output: 5.0
Click me to see the solution

39. Write a C program to calculate the sum of all number divisible by 17 between two given integer numbers. Go to the editor
Test Data :
Input the first integer: 50 Input the second integer: 99
Expected Output:
Sum: 3521
Click me to see the solution

40. Write a C program to find all numbers which dividing it by 7 and the remainder is equal to 2 or 3 between two given integer numbers. Go to the editor
Test Data :
Input the first integer: 25
Input the second integer: 45
Expected Output:
30
31
37
38
44
Click me to see the solution

41. Write a C program to print 3 numbers in a line, starting from 1 and print n lines. Accept number of lines (n, integer) from the user. Go to the editor
Test Data :
Input number of lines: 5
Expected Output:
1 2 3
4 5 6
7 8 9
10 11 12
13 14 15
Click me to see the solution

42. Write a C program to print a number, it’s square and cube in a line, starting from 1 and print n lines. Accept number of lines (n, integer) from the user. Go to the editor
Test Data :
Input number of lines: 5
Expected Output:
1 1 1
2 4 8
3 9 27
4 16 64
5 25 125
Click me to see the solution

43. Write a C program that reads two integers p and q, print p number of lines in a sequence of 1 to b in a line. Go to the editor
Test Data :
Input number of lines: 5
Number of characters in a line: 6
Expected Output:
1 2 3 4 5 6
7 8 9 10 11 12
13 14 15 16 17 18
19 20 21 22 23 24
25 26 27 28 29 30
Click me to see the solution

44. Write a C program to calculate the average marks of mathematics of some students. Input 0 (excluding to calculate the average) or negative value to terminate the input process. Go to the editor
Test Data :
Input Mathematics marks (0 to terminate): 10
15
20
25
0
Expected Output:
Average marks in Mathematics: 17.50
Click me to see the solution

45. Write a C program to calculate the value of S where S = 1 + 1/2 + 1/3 + … + 1/50. Go to the editor
Expected Output:
Value of S: 4.50
Click me to see the solution

46. Write a C program to calculate the value of S where S = 1 + 3/2 + 5/4 + 7/8. Go to the editor
Expected Output:
Value of series: 4.62
Click me to see the solution

47. Write a C program that reads an integer and find all its divisor. Go to the editor
Test Data:
Input an integer: 45
Expected Output:
All the divisor of 45 are:
1
3
5
9
15
45
Click me to see the solution

48. Write a C program to read and print the elements of an array of length 7, before print replace every negative number, zero with 100. Go to the editor
Test Data:
Input the 5 members of the array:
25
45
35
65
15

Expected Output:
Array values are:
n[0] = 25
n[1] = 45
n[2] = 35
n[3] = 65
n[4] = 15
Click me to see the solution

49. Write a C program to read and print the elements of an array of length 7, before print, put the triple of the previous position starting from the second position of the array. Go to the editor
For example, if the first number is 2, the array numbers must be 2, 6, 18, 54 and 162
Test Data:
Input the first number of the array: 5
Expected Output:
n[0] = 5
n[1] = 15
n[2] = 45
n[3] = 135
n[4] = 405
Click me to see the solution

50. Write a C program to read an array of length 5 and print the position and value of the array elements of value less than 5. Go to the editor
Test Data:
Input the 5 members of the array:
15
25
4
35
40
Expected Output:
A[2] = 4.0
Click me to see the solution

51. Write a C program to read an array of length 6, change the first element by the last, the second element by the fifth and the third element by the fourth. Print the elements of the modified array. Go to the editor
Test Data:
Input the 5 members of the array:
15
20
25
30
35

Expected Output:
array_n[0] = 35
array_n[1] = 30
array_n[2] = 25
array_n[3] = 20
array_n[4] = 15
Click me to see the solution

52. Write a C program to read an array of length 6 and find the smallest element and its position. Go to the editor
Test Data:
Input the length of the array: 5 Input the array elements:
25
35
20
14
45
Expected Output:
Smallest Value: 14
Position of the element: 3
Click me to see the solution

## Practice online

```#include <stdio.h>
int main()
{
}```