typedef unsigned char BYTE;
typedef unsigned short WORD;
#define MEM_SZ 1024 //PC is WORD
int main(char *argv[], int argc)
{
    BYTE mem[MEM_SZ];
    *(mem + MEM_SZ - 3) = 0x00;
    *(mem + MEM_SZ - 4) = 0x01;
    WORD *pc = (mem + MEM_SZ-2);
    BYTE a = 0, b = 0; char c = 0;
    while (*pc < MEM_SZ-4)
    {
        a = mem[*pc];
        b = mem[*pc+1];
        c = (char)mem[*pc+2];
        mem[a] = mem[b] - mem[a];
        if (mem[b] == 0) *pc += c;
        else *pc += 3;
    }
    return 0;
}