#include <iostream>
using namespace std;
#define MAX_SIZE 1000
#define check cout << "OK" << endl;

int main() {
    int block_sizes[MAX_SIZE];

    int block_num;
    cin >> block_num;

    if (!cin || MAX_SIZE < block_num) {
        exit(100);
    }

    int max_size = block_num;
    int cnt = 0;
    int ans;

    for (int i = 0; i < block_num; i++) {
        cin >> block_sizes[i];
        if (!cin) {
            exit(100);
        }
    }

    for (int i = block_num - 1; i >= 0; i--) {
        if (block_sizes[i] == max_size) {
            cnt++;
            max_size--;
        }
    }

    ans = block_num - cnt;
    cout << ans << endl;

    return 0;
}