#include<iostream>
#include<cmath>
#include<iomanip>
#include <algorithm>
#include<string>//引入一堆头文件以备不时之需

using namespace std;

int Binary(long long t)
{
	int a[100] = {};
	int x;
	for (x = 0; t / 10; x++)
	{
		a[x] = t % 10;
		t = t / 10;
	}
	a[x] = t;
	int maxbin = 0;
	for (int y = 0; y < x + 1; y++)
		maxbin = max(maxbin, a[y]);
	return maxbin;
}

long long Changebin(long long before, int cnum)
{
	long long after = 0;
	int b[1000] = {};
	int x;
	for (x = 0; before / 10; x++)
	{
		b[x] = before % 10;
		before /= 10;
	}
	b[x] = before;
	for (int j = 0; j < x + 1; j++)
		after += b[j] * pow(cnum, j);
	return after;
}

int main(void)
{
	long long p, q, r;
	long long p1, q1, r1;
	cin >> p >> q >> r;
	int binarynum = max(Binary(p),max(Binary(q),Binary(r)));
	int i;
	for (i = binarynum ; i < 17; i++)
	{
		p1 = Changebin(p, i);
		q1 = Changebin(q, i);
		r1 = Changebin(r, i);
		if (p1 * q1 == r1)
			break;
	}
	if (i == 17)
		i = 0;
	cout << i;
}