PHP Exercises: Remove duplicates from a sorted list

PHP: Exercise-35 with Solution

Write a PHP program to remove duplicates from a sorted list.

Input: (1,1,2,2,3,4,5,5)
Output: (1,2,3,4,5)

Sample Solution: -

PHP Code:

function remove_duplicates_list($list1) {
  $nums_unique = array_values(array_unique($list1));
  return $nums_unique ;
$nums = array(1,1,2,2,3,4,5,5);

Sample Output:

    [0] => 1                                                
    [1] => 2                                                
    [2] => 3                                                
    [3] => 4                                                
    [4] => 5                                                


Flowchart: Remove duplicates from a sorted list.

PHP Code Editor:

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Previous: Write a PHP program to check if the bits of the two given positions of a number are same or not.
Next: Write a PHP program to test if a given string occurs at the end of another given string.

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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:

$first_key = key($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