#include<bits/stdc++.h>
using namespace std;
#define lowbit(x) x&(-x)
#define endl '\n'
int mn[100005],tag[100005],a[100005];
int dp[100005][105],mx[100005][105];
vector<int>pos[100005];
int n,m;
signed main(){
	cin >> n >> m;
	for(int i = 1;i<=n;i++)cin >> a[i];
	vector<int>p;
	for(int i = 1;i<=n;i++){
		p.push_back(a[i]);
	}sort(p.begin(),p.end());p.erase(unique(p.begin(),p.end()),p.end());
	for(int i = 1;i<=n;i++){
		a[i] = lower_bound(p.begin(),p.end(),a[i])-p.begin()+1;
		pos[a[i]].push_back(i);
	}for(int j = 1;j<=m;j++){
		memset(mn,0,sizeof(mn));memset(tag,0,sizeof(tag));
		for(int i = 1;i<=n;i++){
			mn[a[i]] = max(mn[a[i]],mx[i-1][j-1]-tag[a[i]]);tag[a[i]]++;
			dp[i][j] = mn[a[i]]+tag[a[i]];
			mx[i][j] = max(mx[i-1][j],dp[i][j]);
		}
	}int ans =0;
	for(int i = 1;i<=n;i++){
		ans = max(ans,dp[i][m]);
	}cout << ans << endl;
	return 0;
}