Two sum

two_sum.cpp

class Solution {
public:
    vector<int> twoSum(vector<int>& nums, int target) {
        vector<int> res;
        map<int, int> numMap;
        int size = nums.size();
        
        if (size < 2) {
            return res;
        }
        
        for (int i = 0; i < size; i ++)
        {
            numMap.insert(pair<int, int>(nums[i], i));
        }
        
        map<int, int>::iterator iter;
        for (int i = 0; i < size; i ++)
        {
            if ((iter = numMap.find(target - nums[i])) != numMap.end()) {
                if (i == iter->second)      // repeat
                    continue;
                cout << nums[i] << nums[iter->second];
                res.push_back(i);
                res.push_back(iter->second);
                return res;
            }
        }
        
        return res;
    }
};