有人可以解释这个 for 循环是如何工作的吗？

Question

此函数返回数组中的最大数。我需要帮助来理解 if 部分：if (arr[i] > maxNumber) {maxNumber = arr[i]}。使用伪代码或解释这究竟是如何工作的？

function max(arr){

    let maxNumber = 0

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

        if (arr[i] > maxNumber){

            maxNumber = arr[i]

        }

    }

    return maxNumber

}

console.log(max([1,2,3,40,5]));

Answer 1

function max(array) {&nbsp; &nbsp; largest number is equal to 0;&nbsp; &nbsp; for (i is equal to 0; i is less than the length of array; increment i by 1 each time) {&nbsp; &nbsp; &nbsp; &nbsp; if (the item at the current index is greater than the previous largest number) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; set the largest number to to the item at the current index;&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; }&nbsp; &nbsp; return largest number which will be 0 if no larger number is found}值得注意的是，如果数组中的所有值都是负数，它将返回 0；这也适用于负数。function max(arr){&nbsp; &nbsp; let maxNumber = -Infinity&nbsp; &nbsp; for (i = 0; i < arr.length; i++) {&nbsp; &nbsp; &nbsp; &nbsp; if (arr[i] > maxNumber){&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; maxNumber = arr[i]&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; }&nbsp; &nbsp; return maxNumber}

Answer 2

这部分：if (arr[i] > maxNumber) {maxNumber = arr[i]}做的是检查当前数组成员是否大于当前 maxNumber 以及它是否正在将 maxNumber 值更改为当前数组。简而言之，max(whatEverArray)将始终返回零或数组的最大值。如果它返回零，则意味着所有数组值都为零或小于零。