POJ ( acm.pku.edu.cn ) 1049

之前由于使用 char 而非 unsighed char 数据类型吃了苦头。

#include <iostream>
#include <utility>
#include <cstring>
#include <cstdio>
#include <cstdarg>
using namespace std;
#if 0
void dbg_print(char* fmt, ...){
    va_list vl;
    va_start(vl,fmt);
    vfprintf(stderr,fmt,vl);
    va_end(vl);
}
#else
#define dbg_print(...) /*nothing*/
#endif
inline unsigned char to_int(char c){
  if(c>='A'){
      c-=('A'-10);
  } else {
      c-='0';
  }
  return c;
}
inline unsigned char to_hex(char c){
  if(c>=10){
      c+='A'-10;
  } else {
      c+='0';
  }
  return c;
}
inline unsigned char to_address(char high,char low){
  return (to_int(high)<<4|to_int(low));
}
void operate(char* mem){
  unsigned char A=0,B=0,address,tmp;
  for(char* m=mem;*m&&*m!='8';++m){
      switch(*m){
          case '0':
              address=to_address(m[1],m[2]);
              m+=2;
              A=to_int(mem[address]);
              dbg_print("    [debug]  %c%c%c\t read  A ( %01X ) from mem ( %02X )\n",*(m-2),*(m-1),*m,A,address);
              break;
          case '1':
              address=to_address(m[1],m[2]);
              m+=2;
              mem[address]=to_hex(A);
              dbg_print("    [debug]  %c%c%c\t write A ( %01X ) to mem ( %02X )\n",*(m-2),*(m-1),*m,A,address);
              break;
          case '2':
              tmp=A;A=B;B=tmp;
              dbg_print("    [debug]  %c\t\t swap A and B, got: A ( %01X ) B ( %01X )\n",*m,A,B);
              break;
          case '3':
              tmp=A+B;
              A=tmp&0xf;
              B=tmp>>4;
              dbg_print("    [debug]  %c\t\t add A and B, got: A ( %01X ) B( %01X )\n",*m,A,B);
              break;
          case '4':
              ++A; if(A>=16) A=0;
              dbg_print("    [debug]  %c\t\t inc A, got: A ( %01X )\n",*m,A);
              break;
          case '5':
              --A; if(A<0) A=0xf;
              dbg_print("    [debug]  %c\t\t dec A, got: A ( %01X )\n",*m,A);
              break;
          case '6':
              address=to_address(m[1],m[2]);
              m+=2;
              if(A==0){
                  m=mem+address-1;
                  dbg_print("    [debug]  %c%c%c\t bz, go to address %02X\n",*(m-2),*(m-1),*m,address);
                  break;
              }
              dbg_print("    [debug]  %c%c%c\t bz, go on\n",*(m-2),*(m-1),*m);
              break;
          case '7':
              address=to_address(m[1],m[2]);
              m+=2;
              m=mem+address-1;
              dbg_print("    [debug]  %c%c%c\t jump to address %02X\n",*(m-2),*(m-1),*m,address);
              break;
          case '8':
              break;
      }
  }
}
void print(char* mem){
  puts(mem);
}
int main() {
  for(char mem[257];gets(mem);){
      if(mem[0]=='8')break;
      operate(mem); print(mem);
  }
  return 0;
}