algorithm_learning/permutations.php at develop · echojust/algorithm_learning

Repository navigation

<?php

class Solution {

private $result = [];

/**

* 给定一个不含重复数字的数组 nums ，返回其所有可能的全排列。你可以按任意顺序返回答案。

* @param Integer[] $nums

* @return Integer[][]

function permute($nums) {

$this->backTrack($nums, 0, []);

return $this->result;

}

function backTrack($nums, $step, $path) {

if($step == count($nums)){

$arr = $path;

$this->result[] = $arr;

return;

}

for ($i = 0; $i < count($nums); $i++){

if(in_array($nums[$i], $path)){

continue;

}

$path[] = $nums[$i];

$this->backTrack($nums, $step + 1, $path);

array_pop($path);

}