Home Backend Development PHP Tutorial PHP implements the method of outputting the arrangement or combination of multiple elements

PHP implements the method of outputting the arrangement or combination of multiple elements

May 24, 2018 pm 05:13 PM
php element arrangement

This article mainly introduces the method of outputting the arrangement or combination of multiple elements in PHP. Interested friends can refer to it. I hope it will be helpful to everyone.

Examples are as follows:

<?php
$arr = array(&#39;a&#39;,&#39;b&#39;,&#39;c&#39;,&#39;d&#39;);
$result = array();
$t = getCombinationToString($arr, 1);
print_r($t);
$t = getCombinationToString($arr, 2);
$t2 = getunique($t);
print_r($t2);
$t = getCombinationToString($arr, 3);
$t2 = getunique($t);
print_r($t2);
$t = getCombinationToString($arr, 4);
$t2 = getunique($t);
print_r($t2);

function getunique($t){
	$t2 = array();
	//print_r($t);
	for($i=0;$i<count($t);$i++){
		$count_list = array_count_values($t[$i]);
		$flag = 1;
		foreach($count_list as $ck=>$cv){
			if($cv>1){
				$flag = 0;
				break;
			}
		}
		if($flag){
			sort($t[$i]);
			$flag2 = 1;
			if($t2){
				foreach($t2 as $t2k=>$t2v){
					if($t[$i]==$t2v){
						$flag2 = 0;
						break;
					}
				}
			}
			if($flag2){
				$t2[] = $t[$i];
			}
		}
	}
	return $t2;
}

function getCombinationToString($arr, $m) {
	if ($m ==1) {
	 return $arr;
	}
	$result = array();
	
	$tmpArr = $arr;
	unset($tmpArr[0]);
	for($i=0;$i<count($arr);$i++) {
		$s = $arr[$i];
		$ret = getCombinationToString(array_values($tmpArr), ($m-1), $result);
		
		foreach($ret as $row) {
			//$result[] = $s . $row;
			$temp = array();
			$temp[] = $s;
			if(is_array($row)){
				$temp = array_merge($temp,$row);
			}else{
				$temp[] = $row;
			}
			sort($temp);
			$result[] = $temp;
		}
	}
 return $result;
}

?>
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There are 15 permutations in total.

The above is the entire content of this article, I hope it will be helpful to everyone's study.


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