solutia optima pentru 2Sum

2sum-leetcode.cpp

class Solution {


	  public:
	  vector<int> twoSum(vector<int> &nums, int target) {

	  	  map<int,int> mp;

	  	  int n = num.size();

	  	  for(int i = 0; i < n; ++i) {

	  	  	  int a = nums[i];

	  	  	  int b = target - a; //calculezi complementarul.

	  	  	  if( mp.find(b) != mp.end() ) {

	  	  	  	 return { mp[ b ], i };
	  	  	  }

	  	  	  mp[ a ] = i;
	  	  }

	  	  return {-1,-1};
	  } 
}