#include <iostream>
#include <iomanip>
#include <vector>
#include <algorithm>
#include <utility>
#include <string>
#include <queue>
#include <stack>
#include <unordered_set>
#include <unordered_map>

using namespace std;

typedef long long int ll;
typedef pair<int, int> Pii;

const ll mod = 998244353;

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);

  int n;
  cin >> n;
  int a, b;
  cin >> a >> b;
  vector<int> p(n);
  for (auto &x: p) cin >> x;

  int a_rem = a;
  int b_rem = b;
  for (int i = 0; i < n; i++) {
    if (p[i] == 1) {
      a_rem--;
    }
    else if (p[i] == 2) {
      b_rem--;
    }
    else if (p[i] == 3) {
      a_rem--;
      b_rem--;
    }
    if (a_rem < 0 || b_rem < 0) {
      cout << i + 1 << endl;
      return 0;
    }
  }

  cout << -1 << endl;

  return 0;
}