//Divide and Conqueor - Rezwan Arefin
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int maxn = 3.5e4 + 10;
int dp[55][maxn], arr[maxn], par[maxn], prv[maxn];
int n, k;

void scanF(int &x){
    register int c = getchar();
    x = 0;
    for(;(c<48 || c>57);c = getchar());
    for(;c>47 && c<58;c = getchar()) {x = (x<<1) + (x<<3) + c - 48;}
}

void solve(int k, int l, int r, int opl, int opr) {
	if(l > r) return;
	int mid = l + r >> 1, idx = -1, cost = 0;
	for(int i = min(opr+1, mid); i <= mid; i++)
		if(par[i] > mid) cost++;

	for(int i = min(opr, mid-1); i >= opl; i--) {
		int c = dp[k-1][i] + cost;
		if(c > dp[k][mid])
			dp[k][mid] = c, idx = i;
		if(par[i] > mid) cost++;
	}
	solve(k, l, mid-1, opl, idx);
	solve(k, mid+1, r, idx, opr);
}
int main(int argc, char const *argv[]) {
#ifdef LOCAL_TESTING
	freopen("in", "r", stdin);
#endif
	scanF(n); scanF(k);
	for(int i = 1; i <= n; i++)
		scanF(arr[i]);

	for(int i = n; i >= 1; i--) {
		if(prv[arr[i]] == 0) prv[arr[i]] = n+1;
		par[i] = prv[arr[i]];
		prv[arr[i]] = i;
	}

	for(int i = 1; i <= k; i++) {
		solve(i, 0, n, 0, n);
	}
	printf("%d\n", dp[k][n]);
}