The first chapter game music Chinese Chess Generals problem __ Chinese chess generals problem

Requires only one variable to be implemented with a handsome position shown:

Solution One: Universal thinking

#define HALF_BITS_LENGTH 4

This value is half the length of the memory storage unit, which is 4bit in this question.

#define FULLMASK 255

This number represents the mask of a whole bit, in binary notation, it is 11111111.

#define LMASK (Fullmask << half_bits_length)

This macro represents the mask of left bits, in binary notation, which is 11110000.

#define RMASK (Fullmask >> half_bits_length)

This number represents the mask of right bits, in binary notation, which represents 00001111.

#define RSET (b, n) (b = (Lmask & B) ^ n))

This macro, set the right side of B to n

#define LSET (b, n) (b = (Rmask & B) ^ (n<< half_bits_length)))

This macro, set the left of B to n

#define Rget (b) (Rmask & B)

This macro gets the value on the right side of B.

#define Lget (b) ((Lmask & B) >>half_bits_length)

This macro gets the value of the left side of B.

#define GRIDW 3

This number represents the line width of the generals move range.

#include <stdio.h>

#define HALF_BITS_LENGTH 4

#define FULLMASK 255

#define LMASK (Fullmask << half_bits_length)

#define RMASK (Fullmask >> half_bits_length)

#define RSET (b, n) (b = (Lmask & B) ^ n))

#define LSET (b, n) (b = (Rmask & B) ^ (n<< half_bits_length)))

#define Rget (b) (Rmask & B)

#define Lget (b) ((Lmask & B) >>half_bits_length)

#define GRIDW 3

int main ()

{

Unsignedchar b;

For (LSET (b, 1); Lget (b) <= GRIDW * GRIDW; LSET (b, (Lget (b) + 1)))

For (RSET (b, 1); Rget (b) <= GRIDW * GRIDW; RSET (b, (Rget (b) + 1)))

if (Lget (b)% GRIDW!= rget (b)% GRIDW)

printf ("A =%d, B =%d\n", Lget (b), Rget (b));

Return0;

Solution Two: Ingenious thinking

struct {

Unsignedchar A:4;

Unsignedchar B:4;

I

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)

printf ("A =%d, B =%d\n", I.A,I.B);