冒泡算法，leetcode第一题

 
let nums = [2,7,11,15]
let target = 9
 
// 空间交换时间
var twoSum = function(nums, target) {
    const map = new Map()
    for(let i = 0; i < nums.length; i++) {
        if(map.has(target - nums[i])) {
            return [map.get(target - nums[i]), i]
        }
        map.set(nums[i], i)
    }
    return []
};
 
const index_arr = twoSum(nums, target)
console.log(index_arr)