Leetcode exercise 2 - sum of two numbers

 vector<int> twoSum(vector<int>& nums, int target) {
    vector<int> vec;
    int size = nums.size();
    for(int i = 0; i < size; i++)
    {
        for(int j = i + 1; j < size; j++)
        {
           if(nums[i] + nums[j] == target)
           {
               vec.push_back(i);
               vec.push_back(j);
               break;
           }
        }
    }

    return vec;
}