class Solution {public:    vector
     
       twoSum(vector
      
       & nums, int target) {        map
       
        hash;        build(nums,hash);        int index2=0;        vector
        
         result;        for(int i=0;i!=nums.size();i++){            index2=target-nums[i];            if(hash.find(index2)!=hash.end()){                if(i+1
         

nums,map

&hash){ for(int i=0;i!=nums.size();i++) hash[nums[i]]=i+1; }};