#include<bits/stdc++.h>
using namespace std;
inline int read()
{
	int x=0,f=1;char ch=getchar();
	while (ch<'0'||ch>'9'){if (ch=='-') f=-1;ch=getchar();}
	while (ch>='0'&&ch<='9'){x=x*10+ch-48;ch=getchar();}
	return x*f;
}
string z;
int a[10005];//从1到n位数变大个，十，百，千，万
int c[10005];//从1到n位数变大个，十，百，千，万
int l;
int u;
int now[10005];
int cnt,ans,tot;
int wei;
int b[10005];//从1到n位数变大个，十，百，千，万
int d[10005];
int zf;
int main()
{
	cin>>z>>l;
	int n=z.length(); 
	for(int i=1;i<=n;i++)c[i]=int(z[n-i]-'0');
	if(c[1]==2||c[1]==3||c[1]==7||c[1]==8)ans=4;
	else if(c[1]==4||c[1]==9)ans=2;
	else if(c[1]==1||c[1]==5||c[1]==6||c[1]==0)ans=1;
	for(int wei=2;wei<=l;wei++)
	{
		for(int i=1;i<=n;i++)now[i]=0,a[i]=c[i];
		for(int ci=1;ci<ans;ci++)
		{
			for(int i=1;i<=wei;i++)
			{
				for(int j=1;j<=wei;j++)
				{
					now[j+i-1]+=a[j]*c[i];
					now[j+1]+=now[j]/10;
					now[j]%=10;
				}
			}
			for(int i=1;i<=n;i++)now[i+1]+=now[i]/10,now[i]%=10;
			for(int i=1;i<=n;i++)a[i]=now[i],now[i]=0;
		}
		for(int i=1;i<=n;i++)b[i]=a[i];
		for(int i=1;i<=n;i++)a[i]=c[i];
		int u=0;
		while(1)
		{
			u++;
			for(int i=1;i<=n;i++)now[i]=0;
			for(int i=1;i<=wei;i++)
			{
				for(int j=1;j<=wei;j++)
				{
					now[j+i-1]+=a[j]*b[i];
					now[j+1]+=now[j]/10;
					now[j]%=10;
				}
			}
			for(int i=1;i<=n;i++)now[i+1]+=now[i]/10,now[i]%=10;
			for(int i=1;i<=n;i++)a[i]=now[i]; 
			zf=0;
			for(int i=1;i<=wei;i++)
			{
				if(now[i]!=c[i])break;
				zf++;
			}
			if(zf==wei)break;
			if(u>10)
			{
				cout<<-1;
				return 0;
			}
		}
		ans*=u;
	}
	cout<<ans;
	return 0;
}

请求大佬帮忙