#include <iostream>
#include <queue>

using namespace std;
queue<int> q;
int m, n;

int find(int x) {
	queue<int> tmp = q;
	for (int i = 0; i < m; i++) {
		if (tmp.front() == x) {
			return 1;
		}
		tmp.pop();
	}
	return 0;
}


int main() {


	cin >> m >> n;
	int x;
	int sum = 0;
	for (int i = 0; i < n; i++) {
		cin >> x;
		if (q.size() < m && !find(x)) {
			q.push(x);
			sum++;
		} else if (q.size() == m && !find(x)) {
			q.pop();
			q.push(x);
			sum++;
		}
	}
	cout << sum;
}