#include <cstdio>
#include <cstring>

int mem[65537] = {

}, st[16];  // mem 为虚拟机内存，共 64KB（懒得搞其他的了，直接拿 int 当 char 使吧）
int ip, sp;

// 内存中的下一个字节
#define NEXT_BYTE mem[(((ip += 1) &= 65535) - 1) & 65535]
// 栈顶
#define ST st[sp]
// 压栈
#define PUSH(d) (st[sp = (sp - 1) & 15] = d)
// 弹栈
#define POP(d) do {d = ST; sp = (sp + 1) & 15;} while (false)
// case-break 的简化
#define CASE(exp, dos) case exp: dos; break
// 内存操作数
#define OPMEM mem[NEXT_BYTE]
// 栈操作数
#define OPST st[(NEXT_BYTE + sp) & 15]
// 基本运算的统一形式
#define CALC(d, op, t) CASE(d, ST = (ST op t))
// 函数调用统一形式
#define FUNC(d, fun, t) CASE(d, ST = fun(ST, t))
// 运算指令集
#define CAFUSET(d, t) CALC(d, +, t);CALC(d + 1, -, t);CALC(d + 2, *, t);CALC(d + 3, /, t);FUNC(d + 4, xchg, t);FUNC(d + 5, gcd, t);FUNC(d + 6, quick_pow, t)

/*
	0x00 end
	0x01 out stack-top
	0x02 read stack-top
	0x03 push mem[a]
	0x04 popstack -> mem
	0x05 popstack -> null
	0x06 stack-top += stack[i]
	0x07 stack-top -= stack[i]
	0x08 stack-top *= stack[i]
	0x09 stack-top /= stack[i]
	0x0A swap(stack-top, stack[i])
	0x0B stack-top = gcd(stack-top, stack[i])
	0x0C stack-top = pow(stack-top, stack[i])
	0x0D stack-top += mem[i]
	0x0E stack-top -= mem[i]
	0x0F stack-top *= mem[i]
	0x10 stack-top /= mem[i]
	0x11 swap(stack-top, mem[i])
	0x12 stack-top = gcd(stack-top, mem[i])
	0x13 stack-top = pow(stack-top, mem[i])
	0x14 goto a
	0x15 goto stack[i]
	0x16 if stack-top == 0 then goto a
	0x17 push stack-top
	0x18 out char(stack-top)
*/

// 交换
inline int xchg(int a, int& b)
{
	int t;
	t = b; b = a;
	return t;
}

// 最大公约数（辗转相除法）
int gcd(int a, int b)
{
	int r = a % b;
	
	while (r)
	{
		a = b;
		b = r;
		r = a % b;
	}
	
	return a;
}

// 乘幂（二分法）
int quick_pow(int a, int b)
{
	if (!b) return 1;
	
	int k = quick_pow(a, b >> 1);
	k *= k;
	
	if (b & 1) k *= a;
	
	return k;
}

// 从文件中读入内存初始值
void read_mem()
{
	memset(mem, 0, sizeof mem);
	
	FILE * fin = fopen("mem.in", "r");
	int i;
	
	for (i = 0; i < 65536 && !feof(fin); i++)
		fscanf(fin, "%X", &mem[i]);
}

// 主函数
int main()
{
	int now;
	
	ip = sp = 0;
	
	while (true)
	{
		now = NEXT_BYTE;
		
		if (now == 0)
			break;
		
		switch (now)
		{
			CASE(1, printf("%d", ST));
			CASE(2, scanf("%d", &ST));
			CASE(3, PUSH(OPMEM));
			CASE(4, POP(OPMEM));
			CASE(5, POP(now));
			CAFUSET(6, OPST);
			CAFUSET(13, OPMEM);
			CASE(20, ip = NEXT_BYTE);
			CASE(21, ip = ST);
			CASE(22, if (!ST) ip = NEXT_BYTE; else NEXT_BYTE);
			CASE(23, now = ST; PUSH(now));
			CASE(24, putchar(ST));
		}
	}
	
	return 0;
}

/*
	A + B Problem :
	0x03, 
	0x02, 
	0x02, 
	0x17, 
	0x02, 
	0x06, 
	0x01, 
	0x01, 
	0x00
*/