#include <bits/stdc++.h> 
#define int unsigned long long
using namespace std;
const int Max = 50;
int a[Max],f[Max][8];
char c;
signed main()
{
	int n,k;
	cin>>n>>k;
	for(int i = 1;i <= n;++ i)
		cin >> c,a[i] = c - '0';
	f[1][0] = a[1];
	for(int i = 1;i <= n;++ i)//枚举到了第几个数字 
	{
		for(int j = 0;j <= min(i - 1,k);++ j)//前面有j个乘号 
		{
			if(j == 0)
				f[i][j] = f[i - 1][j] * 10 + a[i];
			else
			for(int kk = 1;kk < i;++ kk)//前面j - 1个乘号所在的位置
			{
				int ans = 0;
				for(int z = kk + 1;z <= i;++ z)
					ans = ans * 10 + a[z];
				f[i][j] = max(f[i][j],f[kk][j - 1] * ans);
			}
		}
	}
	cout << f[n][k];
	return 0;
}

#include <cstdio>  
#include <cstring>  
#include <algorithm>  
using namespace std;  
const int power = 4;
const int base = 10000; 
const int MAXL = 106;  
struct num  
{  
    int a[MAXL];  
    num() {memset(a,0,sizeof a);} 
    num(char *s)                                  
    {  
        memset(a, 0, sizeof(a));  
        int len = strlen(s);  
        a[0] = (len+power-1) / power;                     
        for (int i=0, t=0, w; i < len ;w *= 10, ++i)          
        {  
            if (i % power == 0) { w = 1, ++t; }  
            a[t] += w * (s[i]-'0');  
        }  
    }  
    void add(int k) { if (k || a[0]) a[ ++a[0] ] = k; }  
    void re() { reverse(a+1, a+a[0]+1); } 
    void print()                                      
    {  
        printf("%d", a[ a[0] ]);        
        for (int i = a[0]-1;i > 0;--i)  
        printf("%0*d", power, a[i]);      
        printf("\n");  
    }  
} dp[46][46][16],cc;  
bool operator < (const num &p, const num &q)  
{  
    if (p.a[0] < q.a[0]) return true;  
    if (p.a[0] > q.a[0]) return false;  
    for (int i = p.a[0];i > 0;--i)  
    {  
        if (p.a[i] != q.a[i]) return p.a[i] < q.a[i];  
    }  
    return false;  
}     
num operator * (const num &p, const num &q)                    
{  
    num c;  
    c.a[0] = p.a[0]+q.a[0]-1;  
    for (int i = 1;i <= p.a[0];++i)  
    for (int j = 1;j <= q.a[0];++j)  
    {  
        c.a[i+j-1] += p.a[i]*q.a[j];  
        c.a[i+j] += c.a[i+j-1] / base;  
        c.a[i+j-1] %= base;  
    }  
    if (c.a[ c.a[0]+1 ]) ++c.a[0];  
    return c;
}  
int n,k,cnt;
char fz[MAXL],zh[MAXL];
int main()  
{  
	register int i,j,kk,len,l,sl;
	scanf("%d%d%s",&n,&k,&fz);
	for(i=1;i<=n;i++)
		for(j=1;j<=n;j++)
		{
			cnt=0;memset(zh,0,sizeof zh);
			for(kk=i-1;kk<j;kk++) zh[cnt++]=fz[kk];
			reverse(zh,zh+strlen(zh));
			dp[i][j][0]=num(zh);
		}
	for(l=1;l<=k;l++)
		for(len=2;len<=n;len++)
			for(i=1;i<=n-len+1;i++)
			{
				j=i+len-1;
				for(sl=0;sl<l;sl++)
				for(kk=i+1;kk<=j;kk++)
				{
						cc=dp[i][kk-1][sl]*dp[kk][j][l-sl-1];
						if(dp[i][j][l]<cc) dp[i][j][l]=cc;
				}
			}
	dp[1][n][k].print();
	return 0;
}