PHP Array Exercises : Remove duplicate values from an array which contains only integers or strings
39. Remove Duplicate Values from Array
Write a PHP program to remove duplicate values from an array which contains only strings or only integers.
Sample Solution:
PHP Code:
<?php
// Define an array of colors
$colors = array(
0 => 'Red',
1 => 'Green',
2 => 'White',
3 => 'Black',
4 => 'Red',
);
// Define an array of numbers
$numbers = array(
0 => 100,
1 => 200,
2 => 100,
3 => -10,
4 => -10,
5 => 0,
);
// Use array_flip to swap keys and values, then use array_keys to extract unique values
$uniq_colors = array_keys(array_flip($colors));
// Use array_flip to swap keys and values, then use array_keys to extract unique values
$uniq_numbers = array_keys(array_flip($numbers));
// Display the array of unique colors
print_r($uniq_colors);
// Display the array of unique numbers
print_r($uniq_numbers);
?>
Output:
Array ( [0] => Red [1] => Green [2] => White [3] => Black ) Array ( [0] => 100 [1] => 200 [2] => -10 [3] => 0 )
Flowchart:

For more Practice: Solve these Related Problems:
- Write a PHP script to remove duplicate strings from an array without using array_unique(), using a manual iteration approach.
- Write a PHP function to eliminate duplicate integers from an array and then sort the resulting unique values.
- Write a PHP program to compare two arrays and output the difference as a new array containing unique values only.
- Write a PHP script to implement duplicate removal from an array of strings using a custom algorithm that preserves original order.
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