#include <bits/stdc++.h>
using namespace std;
const int N = 1e3 + 5;
const int M = 3e3 + 5;
int t, m;
int a[N], b[N];
int cnt, ans;
int v[N];
int f[N][40];

int main() {
	cin >> t >> m;
	for (int i = 1; i <= t; i++) {
		cin >> a[i];
		if (a[i] != a[i - 1]) {//对于相连的同一棵树的苹果合并为一个物品
			v[++cnt]++;
			b[cnt] = a[i];
		} else {
			v[cnt]++;
		}
	}
	m++;
	if (a[1] == 1)
		m++;
	for (int i = 1; i <= cnt; i++) {
		for (int j = 1; j <= m; j++) {
			int d = max(f[i - 2][j], f[i - 1][j - 1] ) + v[i];
			f[i][j] = max(f[i][j], d);
		}
	}
	for (int i = 1; i <= m; i++) {
		ans = max(ans, f[cnt][i]);
	}
	cout << ans;
	return 0;
}