<?php
// function to generate and print all N! permutations of $str. (N = strlen($str)).
function permute($str,$i,$n,$len)
{
global $ret;
if ($i == $n)
{
if(in_array(substr($str,0,$len),$ret)==false){$ret[]=substr($str,0,$len);}
}else {
for ($j = $i; $j < $n; $j++) {
swap($str,$i,$j);
permute($str, $i+1, $n, $len);
swap($str,$i,$j); // backtrack.
}
}
}
// function to swap the char at pos $i and $j of $str.
function swap(&$str,$i,$j) {
$temp = $str[$i];
$str[$i] = $str[$j];
$str[$j] = $temp;
}
$ret = array();
$str = "123";
permute($str,0,2, 3); // call the function.
?>
- Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
preferences:
198.9 ms | 406 KiB | 312 Q