What is you say is correct but, I submitted the brute force one and it's accepted!! I think as the size is 150 its accepted. Here's my solution.

int main() {
    fastIO
    int n;
    cin>>n;
    vector<int> v(n);
    for(int i =0; i<n; i++){
        int x, y;
        cin>>x>>y;
        v[i] = x-y;
    }
    std::set<int> s;
    s.insert(0);
    for(int i = 0; i<n; i++){
        vector<int> x1(all(s));
        std::set<int> s1;
        for(auto x : x1){
            int a = abs(x-v[i]);
            int b = abs(x+v[i]);
            s1.insert(a);