#include<iostream>
#include<vector>
#include<algorithm>

int main() {
	int n;

	std::cin >> n;

	std::vector<int> v(n);

	for (int i = 0; i < n; i++) {
		std::cin >> v[i];
	}

	int count = 0;
	for (int i = 1; i < n; i++) {
		auto it = std::find(v.begin(), v.end(), i);
		if (it - v.begin() != 0) {
			count++;
		}
		v.erase(it);
	}

	std::cout << count << std::endl;
	return 0;
}