Step by Step solution about How to resolve the algorithm Sorting algorithms/Selection sort step by step in the PHP programming language

The code provided includes two versions of the selection sort algorithm:

Version 1 - Using For Loops:

This version of the algorithm takes a reference to an array as input and performs the following steps:

1. Initialize a variable $n to the count of elements in the array.
2. Iterate over each element in the array using a for loop from $i = 0 to $n.
3. Within this loop, find the index of the minimum element in the remaining unsorted portion of the array. To do this, initialize $min to $i and iterate through the remaining elements (starting from $j = $i + 1). If any element is found to be less than the current minimum, update $min to the index of that element.
4. Swap the element at index $i with the element at index $min to put the minimum element in its correct position.

Version 2 - Using Recursion:

This version uses recursion to implement the selection sort algorithm:

1. It takes two arguments: the input array $arr and an optional $result array (which is initially empty).
2. If the input array is empty, it returns the $result array.
3. It finds the minimum value in the $arr array and adds it to the $result array.
4. It removes the minimum value from the $arr array and calls the selectionsort function recursively with the modified array and the updated $result array.

This recursive version continues until the input array is empty, at which point it returns the sorted $result array.

function selection_sort(&$arr) {
    $n = count($arr);
    for($i = 0; $i < count($arr); $i++) {
        $min = $i;
        for($j = $i + 1; $j < $n; $j++){
            if($arr[$j] < $arr[$min]){
                $min = $j;
            }
        }
        list($arr[$i],$arr[$min]) = array($arr[$min],$arr[$i]);
    }
}


function selectionsort($arr,$result=array()){
    if(count($arr) == 0){
        return $result;
    }
    $nresult = $result;
    $nresult[] = min($arr);
    unset($arr[array_search(min($arr),$arr)]);
    return selectionsort($arr,$nresult);	
}