如何在php中求和具有相同键的单个维数组的值

Question

例如：如果 strArr 是 [“B：-1”、“A：1”、“B：3”、“A：5”]，那么你的程序应该返回字符串 A：6，B：2。

最终的输出字符串应按字母顺序返回键。排除求和后值为 0 的键。示例输入： 数组（“X：-1”， “Y：1”， “X：-4”， “B：3”， “X：5”） 输出： B：3，Y：1

Answer 1

简单的家庭作业。您必须将每对放入一个数组中，并对每个字母的值求和。然后排序 （按键），检查并跳过生成的数组中是否有 0：explodeksort<?php&nbsp; &nbsp; $sums = array();&nbsp; &nbsp; $arr = array("X:-1", "Y:1", "X:-4", "B:3", "X:5");&nbsp; &nbsp; foreach ($arr as $key => $pair) {&nbsp; &nbsp; &nbsp; &nbsp; $pairArray = explode(":", $pair);&nbsp; &nbsp; &nbsp; &nbsp; (!array_key_exists($pairArray[0], $sums))&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; ? $sums[$pairArray[0]] = (int)$pairArray[1]&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; : $sums[$pairArray[0]] += (int)$pairArray[1];&nbsp; &nbsp; }&nbsp; &nbsp; print_r($sums);&nbsp; &nbsp; ksort($sums);&nbsp; &nbsp; $result = array();&nbsp; &nbsp; foreach ($sums as $key => $value) {&nbsp; &nbsp; &nbsp; &nbsp; if ($value != 0) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; array_push($result, $key . ":" . $value);&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; }&nbsp; &nbsp; $result = implode(",", $result);&nbsp; &nbsp; echo $result;?>输出：Array(&nbsp; &nbsp; [X] => 0&nbsp; &nbsp; [Y] => 1&nbsp; &nbsp; [B] => 3)B:3,Y:1