C++ :

#include<iostream>  
#include<string>
#define LL long long  
using namespace std;  
int n,k;  
char a[50];  
LL num[50][50];  
LL dp[50][50][10];  
int main()  
{  
    cin>>n>>k;  
    cin>>a;  
    for(int i=0;i<n;i++)  
    {  
        num[i][i]=a[i]-'0';  
        dp[i][i][0]=num[i][i];  
        for(int j=i+1;j<n;j++)  
        {  
            num[i][j]=num[i][j-1]*10+(a[j]-'0');  
            dp[i][j][0]=num[i][j];  
        }  
    }  
    for(int i=0; i<n;i++)  
    {  
        for(int j=i+1;j<n;j++)  
        {  
            for(int kk=1;kk<=k;kk++)  
            {  
                LL maxV=0;  
                for(int m=i;m<=j;m++)  
                {  
                    for(int left=0;left<=kk;left++)  
                    {  
                        if(dp[i][m][left]*dp[m+1][j][kk-left-1]>maxV)  
                            maxV=dp[i][m][left]*dp[m+1][j][kk-left-1];  
                    }  
                }  
                dp[i][j][kk]=maxV;  
            }  
        }  
    }  
    cout<<dp[0][n-1][k];  
    return 0;  
}

Pascal :

var n,k,i,j,l:integer;a:array[0..50] of integer;sum,f:array[0..50,0..50] of int64;ch:char;
function max(x,y:int64):int64;
 begin
  if x>y then exit(x) else exit(y);
 end;
procedure init;
 begin
  readln(n,k);
  fillchar(sum,sizeof(sum),0);
  for i:=1 to n do
   begin
    read(ch);
    val(ch,a[i]);
    sum[i,i]:=a[i];
   end;
  fillchar(f,sizeof(f),0);
  for i:=1 to n-1 do
  for j:=i+1 to n do
  sum[i,j]:=sum[i,j-1]*10+a[j];
  for i:=1 to n do
   f[0,i]:=sum[1,i];
 end;
begin
 init;
 for i:=1 to k do
 for j:=i to n do
 for l:=1 to j do
  f[i,j]:=max(f[i,j],f[i-1,l]*sum[l+1,j]);
 writeln(f[k,n]);
end.