#include <bits/stdc++.h>
#define int long long
using namespace std;

int a[100010], w[4010], dp[4010][4010];
short tr[1010][1010];
// 50%, TLE??

int cost(int L, int R) {
    int mid = (L + R) >> 1;
    return a[mid] * (mid+mid-L-R) - w[mid-1] + w[L-1] + w[R] - w[mid];
}

signed main(){

    int n, K;
    cin >> n >> K;

    for(int i=0;i<n;i++) {
        cin >> a[i];
    }

    sort(a, a+n);

    w[0] = a[0];
    for(int i=1;i<n;i++) {
        w[i] = w[i-1] + a[i];
    }

    for(int i=0;i<n;i++) {
        dp[1][i] = cost(0, i);
    }

    for(int i=2;i<=K;i++) {
        tr[i][n] = n-2;
        for(int j=n-1;j>=i-1;j--) {
            dp[i][j] = 1e18;
            for(int k=tr[i-1][j];k<=tr[i][j+1];k++) {
                int tmp = dp[i-1][k] + cost(k+1, j);
                if(dp[i][j] > tmp) {
                    dp[i][j] = tmp, tr[i][j] = k;
                }
            }
        }
    }

    cout << dp[K][n-1] << endl;
}