leetcode第一题两数之和

/**
 * @param {number[]} nums
 * @param {number} target
 * @return {number[]}
 */
// var twoSum = function (nums, target) {
//     for (let i = 0, j = nums.length - 1; i < j; i++) {
//         for (let x = i + 1, z = nums.length; x < z; x++) {
//             if (nums[i] + nums[x] === target) {
//                 return [i, x];
//             }
//         }
//     }
// };
var twoSum = function (nums, target) {
    for (let i = 0; i < nums.length; i++) {
        for (let j = i+1; j < nums.length; j++) {
            if (nums[i] + nums[j] == target ) {
                return [i, j]
            }
        }
    }
};
console.log(twoSum([1, 2, 3], 4));

//既然是在数组中寻找两个数字的和那么大家第一反应应该都是两个循环

var twoSum = function (nums, target) {
    for (let i = 0; i < nums.length; i++) {
        for (let j = i+1; j < nums.length; j++) {

//简单的来说就是一直循环数组来判断两数之和，在两数之和为target时返回函数
            if (nums[i] + nums[j] == target ) {
                return [i, j]
            }
        }
    }
};
console.log(twoSum([1, 2, 3], 4));