int zhsh (int, int, int, char[], int, int, int);//???????
int main ()
{
	char s[100], u[100];
	int a, b, l, k = 0, i = 0, j = 0, r, l1;
	cin >> a >> s >> b;
	l = strlen(s);
	int sum = 1;
    zhsh (i, j, l, s, k, sum, a);//?????????????????
	if(zhsh (i, j, l, s, k, sum, a) == 0)//??0??????????
		cout << "0" << endl;
	else
	{
		k = zhsh (i, j, l, s, k, sum, a);
        for (j = 0; k != 0; j++)//????0?
		{
			r = k % b;
	        if (r >= 10)//??????????
				u[j] = r - 10 + 'A';
			else
			    u[j] = r + '0';
		    k=k/b;
		}
	    u[j] = '\0';//????????????
	    l1 = strlen(u);
	    for ( j= l1 - 1; j >= 0; j--)
			cout << u[j];
	    cout << endl;
	}
	return 0;
}
int zhsh(int i,int j,int l,char s[],int k,int sum,int a)//???????
{
	for(i = 0, j = l - 1; j >= 0; i++ , j--)
	{
		if(s[j] >= 65)
		{
			if(s[j] >= 97)
				k = k + (s[j] - 87) * sum;
			else
				k = k + (s[j] - 55) * sum;
		}
		else
            k = k + (s[j] - 48) * sum;
		    sum = sum * a;
	}
	return k;
}



    