#include<bits/stdc++.h>
using namespace std;
int few(string a,string b,string c)
{
	char m=*max_element(a.begin(),a.end());
	m=max(m,*max_element(b.begin(),b.end()));
	m=max(m,*max_element(c.begin(),c.end()));
	return m-'0'+1;
}
long long zhuan(string s,int yuan)
{
	long long n=0;
	int y;
	int c=yuan;
	for(int i=s.size()-1;i>=0;i--)
	{
		y=s[i]-48;
		n=n+y*yuan/c;
		yuan=yuan*c;
	}
	return n;
}
int main()
{
 	ios::sync_with_stdio(false);
 	string p,q,r;
 	cin>>p>>q>>r;
 	few(p,q,r);
 	for(int b=few(p,q,r);b<=16;b++)
 	{
		long long s=zhuan(p,b)*zhuan(q,b);
		if(s==zhuan(r,b))
		{
			cout<<b;
			return 0;
		}
	}
	cout<<0;
	return 0;
}