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PHP Exercises: Check a flat list for duplicate values

PHP: Exercise-84 with Solution

Write a PHP program to check a flat list for duplicate values. Returns true if duplicate values exists and false if values are all unique.

Sample Solution:

PHP Code:

<?php
// Function definition for 'has_Duplicates' that takes an array of items as a parameter
function has_Duplicates($items)
{
    // Check if the count of items is greater than the count of unique items
    if (count($items) > count(array_unique($items)))
        // If duplicates are found, return 1 (true)
        return 1;
    else
        // If no duplicates are found, return 0 (false)
        return 0;
}

// Call 'has_Duplicates' with an array containing duplicates and display the result using 'print_r'
print_r(has_Duplicates([1, 2, 3, 4, 5, 5])); 

// Display a newline
echo "\n";

// Call 'has_Duplicates' with an array without duplicates and display the result using 'print_r'
print_r(has_Duplicates([1, 2, 3, 4, 5])); 

?>

Explanation:

  • Function Definition:
    • The function has_Duplicates takes a single parameter, $items, which is expected to be an array.
  • Count Comparison:
    • The function checks if the total count of items in the array (count($items)) is greater than the count of unique items in the array (count(array_unique($items))).
  • Return Value:
    • If the count of items is greater than the count of unique items:
      • The function returns 1 (indicating that duplicates are present).
    • If the count of items is equal to the count of unique items:
      • The function returns 0 (indicating that no duplicates are present).
  • Example Usage with Duplicates:
    • The function is called with an array containing duplicates: [1, 2, 3, 4, 5, 5].
    • The result (1) is displayed using print_r, indicating that duplicates are found.
  • Example Usage without Duplicates:
    • The function is called with an array without duplicates: [1, 2, 3, 4, 5].
    • The result (0) is displayed using print_r, indicating that no duplicates are found.
  • Purpose:
    • The has_Duplicates function provides a simple way to check for duplicate values in an array and returns a boolean-like result (1 for true, 0 for false) based on the presence of duplicates.

Output:

1
0

Flowchart:

Flowchart: Check a flat list for duplicate values.

PHP Code Editor:

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