#include <bits/stdc++.h>
using namespace std;
const int INF = 0x3f3f3f3f;
const long long LINF = 0x3f3f3f3f3f3f3f3f;
const long long mod = 1e9 + 7;
const double PI = acos(-1.0);
const double eps = 1e-10;
const int N = 1e5 + 5;
int n;
long long s[N], a, b;
int main() {
  scanf("%d %I64d %I64d", &n, &a, &b);
  long long sum = 0;
  for (int i = 0; i < n; i++) {
    scanf("%I64d", s + i);
    sum += s[i];
  }
  int res = -1;
  if (s[0] * a >= sum * b)
    res = 0;
  else {
    sort(s + 1, s + n, greater<long long>());
    for (int i = 1; i < n; i++) {
      sum -= s[i];
      if (s[0] * a >= sum * b) {
        res = i;
        break;
      }
    }
  }
  printf("%d\n", res);
  return 0;
}
