编程之美---中国象棋将帅问题

来源：互联网发布：时间软件安卓版编辑：程序博客网时间：2024/05/01 02:12

题目链接：http://www.msra.cn/Articles/ArticleItem.aspx?Guid=4c86d636-04bb-4ad9-b0bc-4c3496d18021#.

给出c++实现的简单代码：

#include <iostream>#include <cstdio>using namespace std;const unsigned char fullmark=255; //11111111 const unsigned char L_mask=fullmark<<4;//11110000const unsigned char R_mask=fullmark>>4; //00001111void RSET(unsigned char &b,int n){b=b&L_mask;b=b|n;}void LSET(unsigned char &b,int n){b=b&R_mask;b=b|(n<<4);}unsigned int rget(unsigned char b)//注意这里不能传引用 {b=b&R_mask;return (unsigned int)b;}unsigned int lget(unsigned char b)//不能传引用 {b=b&L_mask;b=b>>4;return (unsigned int)b;}int main(){unsigned char b=0;LSET(b,1);//RSET(b,1);  //注意这里内存初始化不能放在外面 for(;lget(b)<=9;LSET(b,lget(b)+1))for(RSET(b,1);rget(b)<=9;RSET(b,rget(b)+1)){if(lget(b)%3!=rget(b)%3){cout<<"a=: "<<lget(b)<<", b=: "<<rget(b)<<endl;}} return 0;}

这是传统的解法，下面的代码使用了位域的知识，比较简洁：

#include <iostream>using namespace std;struct node {unsigned char a:4;unsigned char b:4;}i;int main(){for(i.a=1;i.a<=9;i.a++)for(i.b=1;i.b<=9;i.b++){if(i.a%3!=i.b%3){cout<<"A=: "<<int(i.a)<<", B=: "<<int(i.b)<<endl;}}return 0;}