作业1

var nums = new Array(2, 5, 7, 11);

// 作业1给定一个数组nums=[2,5,7,11],要求任意两个数组元素和等于指定的值target=9;并返回他们下标，return[0,2]
function ans() {
    var target = 9;
    for (var i = 0; i < nums.length; i++) {
        for (var j = i; j < nums.length; j++) {
            if (nums[i] + nums[j] == target) {
                console.log(new Array(i, j))
            }
        }
    }
}

ans();

// 作业2重构pop方法，要求实现和pop一样的效果
Array.prototype.myPop = function() {
    var ans = this[this.length - 1];
    this.splice(this.length - 1);
    return ans;
}

console.log(nums.myPop(), "myPop结果", nums);

Array.prototype.myPush = function(a) {
    this[this.length] = a;
    return this.length;
}

console.log(nums.myPush(5), "myPush结果", nums);