放入for循环时,排序函数的行为会有所不同

Question

我有两种排序函数,用于排序数字数组并返回前两个索引的总和,但是当这些函数在for循环中运行时,第二个函数不能正常工作.

这是第一个:

function solution(numbers) {
    numbers.sort(function (a, b) { 
        return a - b;
    }); 
    return numbers[0] + numbers[1];
}

这是第二个:

function sumTwoSmallestNumbers(numbers) {
    var findSmallest = function(startsAt){
        var first = startsAt;
        for (var i =0; i<=numbers.length-1; i++){
            if(first >= numbers[i]){
                first = numbers[i];
            }
        }
        return first;
    }
    var smallest = findSmallest(numbers[0]);
    var index = numbers.indexOf(smallest);
    numbers.splice(index,1);
    var secondSmallest = findSmallest(numbers[0]);
    return smallest+secondSmallest
};

这是for循环:

for (let i = 0; i < 100; i++) {
    var randArr = [Test.randomNumber()+1000,Test.randomNumber(),Test.randomNumber(),Test.randomNumber(),Test.randomNumber()];
    var staticArr = [1000, 50,12000, 275, 21000, 1];
    console.log("Result of user function is: " + sumTwoSmallestNumbers(staticArr) + ". Result of own function is: " + solution(staticArr));
    Test.assertEquals(sumTwoSmallestNumbers(randArr), solution(randArr));
}

请参阅小提琴中的控制台:https://jsfiddle.net/emporio/p4r7go57/1/

Answer 1

numbers.splice(index,1);

这会修改输入数组,删除最小的数字.每次调用sumTwoSmallestNumbers一个项目都会被删除,这会在下次调用时更改结果.