编程之美 1.2 中国象棋将帅问题

/*编程之美1.2 中国象棋将帅问题：利用1个字节来输出将帅的合法位置*/

/*方法一：位运算*/#include <iostream> using namespace std;#define LEFT(a) ((a)>>4)#define RIGHT(a) ((a) & 0x0F)#define ADD_LEFT(a) a =( (LEFT(a)+1<<4) | RIGHT(a))#define ADD_RIGHT(a) a = ( (LEFT(a)<<4) | (RIGHT(a)+1))#define INIT_LEFT(a) a = ( (1<<4) | RIGHT(a) )#define INIT_RIGHT(a) a = ( (LEFT(a)<<4) | 1 )#define MATCH(a) (LEFT(a)%3 == RIGHT(a)%3)int main(){//freopen("in.txt", "r", stdin);unsigned char v = 0x11;for(INIT_LEFT(v); LEFT(v)<=9; ADD_LEFT(v)) {for(INIT_RIGHT(v); RIGHT(v)<=9; ADD_RIGHT(v)) if(!MATCH(v)){cout << "A = " << LEFT(v) << ", B = " << RIGHT(v) << endl;}}return 0;}

 /*方法二： 位域  */#include <iostream> using namespace std;struct {unsigned int a : 4;unsigned int b : 4;} i;int main(){//freopen("in.txt", "r", stdin);for(i.a = 1; i.a <= 9; i.a++) {for(i.b = 1; i.b <= 9; i.b++) {cout << "A = " << i.a << ", B = " << i.b << endl;}}return 0;}

//方法三：十进制

#include <iostream>using namespace std;int main(){unsigned char i = 0;for(i = 0; i/10<9; i+=10) {for(i -= i%10; i%10<9; i++) if(i/10%3 != i%10%3){cout << "A = " << i/10+1 << ", B = " << i%10+1 << endl;}}return 0;}

//方法四：九进制 （可以一一对应）

#include <iostream>using namespace std;int main(){int i = 81;while(i--) {if(i/9%3 == i%9%3) continue;cout << "A = " << i/9 + 1 << ", B = " << i%9 + 1 << endl;}return 0;}