题目大意：

 

题解：

#include 
      
       using namespace std;char ch[45];int n,k;long long int arr[45][7];long long int dp[45][7];int main(){    cin >> n >> k >> ch;    for(int i = 0; i < n; i++){        int tmp = 0;        for(int j = i; j < n; j++){            tmp = tmp * 10 + ch[j]-'0';            arr[i][j] = tmp;        }    }    //dp 开始     for(int i = 0; i < n; i++){        dp[i][0] = arr[0][i];     }     for(int i = 0; i < n; i++){        for(int j = 1; j <= k; j++){            for(int k = 0; k < i; k++){                dp[i][j] = max(dp[k][j-1]*arr[k+1][i],dp[i][j]);            }        }     }     cout << dp[n-1][k] << endl;    return 0;}