Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target

Here is a brute force solution:

#include <iostream> 
#include <vector> 
using namespace std;
class Solution { 
public: 
vector<int> twoSum(vector<int>& nums, int target)  {
 int n = nums.size(); 
for (int i=0;i<n;++i) 
for(int j=0;j<n;++j) if(i!=j) if (nums[i] + nums[j] == target) { vector<int> ret{ i,j };
 return ret;
 } 
} 
}; 
int main() 
{
 int target = 7;
 vector<int> nums{ 1,2,3,4 }; vector<int> ret; 
 Solution Sol1;
 ret = Sol1.twoSum(nums, target); 
 cout << "Solution is "; 
 for (auto i = ret.begin(); i != ret.end(); ++i) std::cout << *i << ' '; 
}