void main()
{
	char shurudeshu[1000];int n,shijingzhi=0,i;
	int jingzhi,daizhuanhuandejingzhi;
	scanf("%d ",&jingzhi);scanf("%s ",shurudeshu);scanf("%d",&daizhuanhuandejingzhi);
	n=strlen(shurudeshu);
	for(i=0;i<=n-1;i++)
	{
		if(('A'<=shurudeshu[i])&&(shurudeshu[i]<='Z'))
			shurudeshu[i]=shurudeshu[i]-'A'+10;
		else if(('a'<=shurudeshu[i])&&(shurudeshu[i]<='z'))
			shurudeshu[i]=shurudeshu[i]-'a'+10;
		else if(('0'<=shurudeshu[i])&&(shurudeshu[i]<='9'))
			shurudeshu[i]=shurudeshu[i]-'0';
	}
		for(i=0;i<=n-1;i++)
		{
			shijingzhi=shijingzhi+(int)(shurudeshu[i]*pow(jingzhi,n-i-1));
		}
		if(shijingzhi==0)
			printf("%d",shijingzhi);
		if(shijingzhi!=0)
		{
		int shang;int yushu[100],j;
   shang=shijingzhi;
   for(i=0;shang!=0;i++)
   {
       yushu[i]=shang%daizhuanhuandejingzhi;
       shang=shang/daizhuanhuandejingzhi;
   }
   for(j=i-1;j>=0;j--)
   {
	   if((0<=yushu[j])&&(yushu[j]<=9))
		   printf("%d",yushu[j]);
	   else if(yushu[j]>=10)
	   {
		   yushu[j]=yushu[j]+'A'-10;
	       printf("%c",yushu[j]);
	   }
   }
		}
   printf("\n");
}