为什么没有返回突破这个功能？

Question

在对 coderbyte 进行挑战时，我找到了其他人的解决方案。然而，他的代码不适用于其中一个测试用例，但我不明白为什么。

挑战信息：输入是一个由 2 个字符串组成的数组，第一个字符串包含 2 个数字，表示秤两侧的权重。第二个字符串包含您可以用来尝试平衡秤的权重。目标：用最少的权重（最大 2）平衡秤并输出您使用的权重。

代码输出 1,6，它确实平衡了秤，但秤也可以仅通过一个重量来平衡， 5. 为什么第一个“返回”没有脱离函数？

function ScaleBalancing(strArr) {

    const w1 = JSON.parse(strArr[0])[0];

    const w2 = JSON.parse(strArr[0])[1];

    let weights = JSON.parse(strArr[1]);

    for (let i = 0; i < weights.length; i++) {

        if (w1 + weights[i] === w2 || w2 + weights[i] === w1) {         

            return '' + weights[i]; // should return 5 and break out of function right?

        }

        //if this for loop is omitted the function returns 5

        for (let j = i + 1; j < weights.length; j++) {

            if (w1 + weights[i] + weights[j] === w2 ||

                w2 + weights[i] + weights[j] === w1 ||

                w1 + weights[i] === w2 + weights[j] ||

                w2 + weights[i] === w1 + weights[j]) {

                return '' + weights[i] + ',' + weights[j]; //this returns 1,6

            }

        }

    }

    return 'not possible';

}

// keep this function call here 

ScaleBalancing(["[6, 1]", "[1, 10, 6, 5]"]);

Answer 1

原因是外循环从0索引开始。在那一点上，代码不知道它5会在某个时间出现在数组中。将第一个数字是1条件(w1 + weights[i] === w2 || w2 + weights[i] === w1)是false如此这般嵌套for循环。如果你把5之前1的代码将返回5function ScaleBalancing(strArr) {&nbsp; &nbsp; const w1 = JSON.parse(strArr[0])[0];&nbsp; &nbsp; const w2 = JSON.parse(strArr[0])[1];&nbsp; &nbsp; let weights = JSON.parse(strArr[1]);&nbsp; &nbsp; for (let i = 0; i < weights.length; i++) {&nbsp; &nbsp; &nbsp; &nbsp; if (w1 + weights[i] === w2 || w2 + weights[i] === w1) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; return '' + weights[i]; // should return 5 and break out of function right?&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; //if this for loop is omitted the function returns 5&nbsp; &nbsp; &nbsp; &nbsp; for (let j = i + 1; j < weights.length; j++) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (w1 + weights[i] + weights[j] === w2 ||&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; w2 + weights[i] + weights[j] === w1 ||&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; w1 + weights[i] === w2 + weights[j] ||&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; w2 + weights[i] === w1 + weights[j]) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; return '' + weights[i] + ',' + weights[j]; //this returns 1,6&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; }&nbsp; &nbsp; return 'not possible';}// keep this function call here&nbsp;console.log(ScaleBalancing(["[6, 1]", "[5, 10, 6, 1]"]));