如何在php中获取相同元素的位置？

Question

我需要你的帮助来确定数组中重复或相同元素的位置。例如

$arr =[6,5,3,7,40,45,7,6,3,32,86,40,5,3,7,40];

结果

6 = 0,7

5 =  1,11

3 =  2,8

7 = 3,6,14

40 = 4,11,15

45 =5 and so on.

Answer 1

一种简单的方法：<?php$arr =[6,5,3,7,40,45,7,6,3,32,86,40,5,3,7,40];$pos = array();foreach($arr as $k => $v) {&nbsp; &nbsp;$pos[$v][] = $k;&nbsp; &nbsp;}&nbsp; &nbsp;&nbsp;foreach($pos as $k => $v) {&nbsp; &nbsp;echo $k."=".implode(',', $v)."<br>";&nbsp; &nbsp;}&nbsp; &nbsp;&nbsp;?>结果：6=0,75=1,123=2,8,137=3,6,1440=4,11,1545=532=986=10