func_code_string: #include <bits/stdc++.h>   using namespace std;   vector<pair<long long, long long> > v;   vector<long long> q;   int main() {     long long n, d, a, b, xx, x, y, sum = 0;     cin >> n >> d >> a >> b;     for (long long i = 0; i < n; i++) {       cin >> x >> y;       xx = x * a + y * b;       v.push_back(make_pair(xx, i));     }     sort(v.begin(), v.end());     for (long long i = 0; i < n; i++) {       if (v[i].first + sum <= d) {         q.push_back(v[i].second);         sum += v[i].first;       } else         break;     }     n = q.size();     cout << n << endl;     for (long long i = 0; i < n; i++) {       cout << q[i] + 1 <<    ;     }     return 0;   }   