two_sum.cpp

#include <bits/stdc++.h>
using namespace std;

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

        unordered_map<int, int> mp; // value -> index

        for (int i = 0; i < nums.size(); i++) {

            int remaining = target - nums[i];

            if (mp.find(remaining) != mp.end()) {
                return { mp[remaining], i };
            }

            mp[nums[i]] = i;
        }

        return {};
    }
};

int main() {
    Solution obj;

    vector<int> nums = {2, 7, 11, 15};
    int target = 17;

    vector<int> result = obj.twoSum(nums, target);

    cout << "Indices: ";
    for (int index : result) {
        cout << index << " ";
    }

    return 0;
}