C

#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <algorithm>
#include <unordered_set>
#include <vector>
#include <cmath>
#include <string>
#include <set>
#include <map>
#include <cstdio>
#include <functional>
#include <random>
#include <ctime>
#include <cassert>
#include <bitset>
#include <unordered_map>
#include <math.h>
#include <queue>

using namespace std;

#define N 35005
#define M 55
#define F 200
mt19937 gen(time(NULL));
#define forn(i, n) for (int i = 0; i < n; i++)
#define fornv(i, n) for (int i = n - 1; i >= 0; i--)
#define pii pair<int, int>
#define forlr(i, l, r) for (int i = l; i <= r; i++)
#define forlrv(i, l, r) for (int i = r; i >= l; i--)
#define debug(...) fprintf(stderr, __VA_ARGS__), fflush(stderr)
#define mp make_pair
typedef long long ll;
typedef unsigned long long ull;
const long double eps = 1e-9;
const int inf = 2e9;
const int mod = 1e9 + 7;
const ll infinity = 2 * 1e18;
#define p p2
#define endl '\n'

int t[4 * N], d[4 * N], w[N];

int dp[M][N];

int n, k;

void build(int k, int u, int l, int r)
{
    if (l == r - 1)
        return void(t[u] = dp[k][l]);

    int m = (l + r) / 2;
    build(k, 2 * u + 1, l, m);
    build(k, 2 * u + 2, m, r);
}

void push(int u, int len)
{
    if (!d[u]) return;

    t[u] += d[u];

    if (len > 1)
        d[2 * u + 1] += d[u], d[2 * u + 2] += d[u];

    d[u] = 0;
}

void update(int u, int l, int r, int L, int R)
{
    push(u, r - l);

    if (l == L && r == R)
    {
        d[u]++;
        push(u, r - l);
        return;
    }

    int m = (l + r) / 2;
    if (L < m)
        update(2 * u + 1, l, m, L, min(m, R));
    else
        push(2 * u + 1, m - l);

    if (R > m)
        update(2 * u + 2, m, r, max(L, m), R);
    else
        push(2 * u + 2, r - m);

    t[u] = max(t[2 * u + 1], t[2 * u + 2]);
}

int get(int u, int l, int r, int L, int R)
{
    if (L >= R) return 0;

    push(u, r - l);

    if (l == L && r == R) return t[u];

    int m = (l + r) / 2, ans = 0;

    if (L < m)
        ans = max(ans, get(2 * u + 1, l, m, L, min(m, R)));
    else
        push(2 * u + 1, m - l);

    if (R > m)
        ans = max(ans, get(2 * u + 2, m, r, max(L, m), R));
    else
        push(2 * u + 2, r - m);

    return ans;
}

int p[N];
map<int, int> last;

void solve(int k)
{
    fill_n(t, 4 * N, 0), fill_n(d, 4 * N, 0);

    build(k - 1, 0, 0, n);

    forn(i, n)
    {
        if (p[i] < i)
            update(0, 0, n, p[i], i);
        dp[k][i] = max(dp[k - 1][i], get(0, 0, n, 0, i));
    }
}


int main()
{
    scanf("%d %d", &n, &k);
    forn(i, n) scanf("%d", &w[i]);

    forn(i, n)
    {
        p[i] = -1;
        if (last.count(w[i]))
            p[i] = last[w[i]];
        else
            p[i] = 0;

        last[w[i]] = i;
    }

    set<int> s;
    forn(i, n)
    {
        s.insert(w[i]);
        dp[1][i] = s.size();
    }

    for (int i = 2; i <= k; i++) solve(i);

    printf("%d\n", dp[k][n - 1]);
}