#include <stdio.h>

 #include <stdlib.h>

 #include <string.h>

 #define MAXN 2005

 #define INF  0x3fffffff

 int dp[MAXN][MAXN];

 int buf[MAXN];

 int deg[MAXN];

 int mymin(int a, int b) {

     return (a<b) ? a:b;

 }

 int comp(const void *a, const void *b) {

     return *(int *)a - *(int *)b;

 }

 int main() {

     int n, m, k;

     int i, j;

     while (scanf("%d %d", &n, &k) != EOF) {

         for (i=; i<=n; ++i)

             scanf("%d", &buf[i]);

         qsort(buf+, n, sizeof(int), comp);

         m = ;

         for (i=; i<=n; ++i)

             deg[m++] = (buf[i]-buf[i-])*(buf[i]-buf[i-]);

         for (i=; i<=n; ++i) {

             dp[i][] = ;

             for (j=; j<=k; ++j) {

                 dp[i][j] = INF;

             }

         }

         for (i=; i<=n; ++i) {

             for (j=; j+j<=i; ++j) {

                 dp[i][j] = mymin(dp[i-][j-]+deg[i-], dp[i-][j]);

             }

         }

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

     }

     return ;

 }