#include<bits/stdc++.h>
using namespace std;
using LL = long long;
using ULL = unsigned long long;
#define rep(i,n) for(int i=0; i<(n); i++)

int main() {
    int N; cin >> N;
    int n = N;
    int A[100000]; rep(i, N) cin >> A[i];
    int ans = N;
    for (int i = N - 1; i >= 0; i--)
        if (A[i] == n) { ans--; n--; }
    cout << ans << endl;
    return 0;
}