最近被算法虐了一下，刷一下leetcode，找找存在感

如题：

Given an array of integers, return indices of the two numbers such that they add up to a specific target.

You may assume that each input would have exactly one solution, and you may not use the same element twice.

Example:

Given nums = [2, 7, 11, 15], target = 9,Because nums[0] + nums[1] = 2 + 7 = 9,return [0, 1].

/** * @param {number[]} nums * @param {number} target * @return {number[]} */var twoSum = function(nums, target) {    var arr=[];    for(var i=0;i