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].
class Solution { public: vector<int> twoSum(vector<int>& nums, int target) { int n = nums.size(); map<int, int> m; for(int i=0; i<n; i++) { int temp = target - nums[i]; map<int, int>::iterator it = m.find(temp); if(it != m.end()) { return vector<int> {it->second, i}; } m[nums[i]] = i; } } };