#include < iostream >
using   namespace  std;

int  N,M;
int  f[ 501 ][ 501 ] = { 0 };
int  a[ 501 ] = { 0 };
int  b[ 501 ] = { 0 };
int  main()
{
    cin >> N >> M;
     int  x = 0 ;
     for ( int  i = 1 ;i <= M; ++ i)
         for ( int  j = 1 ;j <= N; ++ j)
            f[i][j] = 0xFFFFFFF ;
     for ( int  i = 1 ;i <= N; ++ i){
        cin >> x;
        a[i] = a[i - 1 ];
        b[i] = b[i - 1 ];
         if (x) a[i] ++ ;
         else  b[i] ++ ;
        f[ 1 ][i] = a[i] * b[i];
    }
     for ( int  i = 2 ;i <= M; ++ i)
         for ( int  j = i;j <= N; ++ j){
             for ( int  t = i - 1 ;t < j; ++ t)
                 if (f[i][j] > f[i - 1 ][t] + (a[j] - a[t]) * (b[j] - b[t]))
                    f[i][j] = f[i - 1 ][t] + (a[j] - a[t]) * (b[j] - b[t]);
        }
    cout << f[M][N] << endl;
     return   0 ;
}