https://leetcode.com/problems/two-sum/

先排序，有序后枚举a，二分查找b，因为必然有解，直接找到就return。

class Solution {public:    struct node    {        int num;        int ord;    };    static bool cmp(node a,node b)        {            return a.num
     
      & temp,int key)    {        while(l<=r)        {            int mid=(l+r)>>1;            if(temp[mid].num==key)                return mid;            if(temp[mid].num>key)                r=mid-1;            if(temp[mid].num
      

twoSum(vector

& nums, int target) { vector

ans; vector

temp; for(int i=0;i