func_code_string: #include <bits/stdc++.h>   using namespace std;   long long n, d, a, b, p[100005], x[100005], y[100005], c, ans[100005];   long long cmp(long long A, long long B) {     return x[A] * a + y[A] * b < x[B] * a + y[B] * b;   }   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cin >> n >> d;     cin >> a >> b;     for (long long i = 1; i <= n; i++) cin >> x[i] >> y[i], p[i] = i;     sort(p + 1, p + 1 + n, cmp);     for (long long i = 1; i <= n; i++)       if (d >= x[p[i]] * a + y[p[i]] * b)         d -= x[p[i]] * a + y[p[i]] * b, ans[++c] = p[i];     cout << c << endl;     for (int i = 1; i <= c; i++) cout << ans[i] <<    ;     cout << endl;     return 0;   }   