#include <iostream>
#include <cstring>
#include <algorithm>

using namespace std;

const int N = 45 , M = 10;

int n , k;
int w[N];
int num[N][N];
int f[N][M];

int main(){

   char ch;
   cin >> n >> k;

   int i = 0;
   while(cin >> ch)
   {
       w[++i] = ch - '0';
   }

    for(int i = 1 ; i <= n ; i++)
       for(int j = i ; j <= n ;j++)
       {
           num[i][j]=num[i][j-1]*10+w[j];
       }

    for(int i = 1 ; i <= n ;i++)f[i][0] = num[1][i]; 

    for(int i = 1 ; i <= n ;i++)
       for(int j = 1 ; j <= k&&j<=i-1 ;j++)
          for(int h = 2 ; h <= i ; h++)
           f[i][j] = max(f[i][j] , f[h - 1][j - 1] * num[h][i]);

        cout << f[n][k] << endl;   
    return 0;
}