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

int main()
{
	int N;
	cin >> N;
	vector<int> P( N );
	for( int i = 0; i < N; i++ ) cin >> P[i];

	for( int i = N - 1; i >= 0; i-- ) {
		if( P[i] == N ) N--;
		else break;
	}
	long long ans = 0;
	for( int i = 0; i < N; i++ ) {
		if( P[i] == N ) ans -= i + 1;
		else ans += i + 1;
	}

	cout << ans << endl;
}