#include<stdio.h>
#include<stdlib.h>
long long powme(long long number, long long cf)
{
	if (cf == 0)
	{
		number = 1;
	}
	for (; cf > 1; cf--)
	{
		number *= number;
	}
	return number;
}
long long transform(long long a, long long b)
{
	long long c=0;
	for (int i = 0; a > 0; i++)
	{
		if (a % 10 < b) {
			c += (a % 10) * powme(b, i);
			a /= 10;
		}
		else {
			break;
			c = 0;
		}
	}
	return c;
}
int main()
{
	long long number1, number2, number3,bl;
	scanf("%lld %lld %lld", &number1, &number2, &number3);
	for (int s = 2; s < 17; s++)
	{
		if ((transform(number1, s) * transform(number2, s)) == transform(number3, s)&& ((transform(number1, s) * transform(number2, s))*transform(number3, s)!=0))
		{
			printf("%d", s);
			bl = 1;
			break;
		}
		else
		{
			bl = 0;
		}
	}
	if (bl)
	{

	}
	else {
		printf("%lld", bl);
	}




	return 0;
}

75求调，题例可过