PHP Exercises: Memoize a given function results in memory

PHP: Exercise-99 with Solution

Write a PHP program to memoize a given function results in memory.

Note: In computing, memoization or memoisation is an optimization technique used primarily to speed up computer programs by storing the results of expensive function calls and returning the cached result when the same inputs occur again.

Sample Solution: -

PHP Code:

<?php
//Licence: https://bit.ly/2CFA5XY
function memoize($func)
{
    return function () use ($func) {
        static $cache = [];

        $args = func_get_args();
        $key = serialize($args);
        $cached = true;

        if (!isset($cache[$key])) {
            $cache[$key] = $func(...$args);
            $cached = false;
        }

        return ['result' => $cache[$key], 'cached' => $cached];
    };
}

$memoizedAdd = memoize(
    function ($num) {
        return $num + 10;
    }
);

var_dump($memoizedAdd(5));  
var_dump($memoizedAdd(6));  
var_dump($memoizedAdd(5));  
?>

Sample Output:

array(2) {
  ["result"]=>
  int(15)
  ["cached"]=>
  bool(false)
}
array(2) {
  ["result"]=>
  int(16)
  ["cached"]=>
  bool(false)
}
array(2) {
  ["result"]=>
  int(15)
  ["cached"]=>
  bool(true)
}

Flowchart:

PHP Code Editor:

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