#include <bits/stdc++.h>
using namespace std;

int main () {
    int n, a, b;
    cin >> n >> a >> b;
    vector<int> p(n);
    for(int i=0; i<n; i++) cin >> p.at(i);
    int cnt_ap=a, cnt_bn=b;
    for(int i=0; i<n; i++) {
        if(p.at(i) == 1) cnt_ap--;
        else if(p.at(i) == 2) cnt_bn--;
        else {
            cnt_ap--;
            cnt_bn--;
        }
        if(cnt_ap<0 || cnt_bn<0) {
            cout << i+1;
            return 0;
        }
    }
    cout << -1;
}