Question

为什么即使在for循环之前就已声明fin变量也未定义？

a  = function(...args) {
    total = 0;
    for (each of args) {
        total += each;
    }
    total = total.toString();
    while (total.length != 1) {
        var fin = 1;
        for (int i = 0; i < total.length; i++) {
            fin *= parseInt(total[i]);
        }
        total = fin.toString();
    }

    return parseInt(fin);
}



a(1,2,3,4,5,6)

Answer 1

如果我删除了您所有的int引用，它将运行正常

a  = function(...args) {
    total = 0;
    for (each of args) {
        total += each;
    }
    total = total.toString();
    while (total.length != 1) {
        var fin = 1;
        for (i = 0; i < total.length; i++) {
            fin *= parseInt(total[i]);
        }
        total = fin.toString();
    }

    return parseInt(fin);
}



var result = a(1,2,3,4,5,6);
console.log('result', result);

[edit]如果我想以更多方式修复它，我可能会这样写：

const a = function(...args) {
    let total = 0;
    for (let each of args) {
        total += each;
    }
    total = total.toString();
    let fin;
    while (total.length != 1) {
        fin = 1;
        for (let i = 0; i < total.length; i++) {
            fin *= parseInt(total[i]);
        }
        total = fin.toString();
    }

    return parseInt(fin);
}



var result = a(1,2,3,4,5,6);
console.log('result', result);

Answer 2

您使用的int关键字以及一些未定义的int对象不存在。您要尝试的是这样：

a  = function(...args) {
    total = 0;
    for (each of args) {
        total += each;
    }
    total = total.toString();
    while (total.length != 1) {
        var fin = 1;
        for (let i = 0; i < total.length; i++) {
            fin *= parseInt(total[i]);
        }
        total = fin.toString();
    }

    return parseInt(fin);
}



console.log(a(1,2,3,4,5,6));

Answer 3

要使此代码正常工作，您需要做几处更改。

JavaScript不会理解诸如 int 之类的东西（因为它不是强类型的），因此在for循环中删除int关键字并改用let或var。

对于（ let ，i = 0； i
您必须使用fin * = Number.parseInt（total [i]）;
来代替 int.parseInt

尽管我已经定义了变量，但据说它没有定义（JavaScript）

3 个答案: