黑白棋

#include <stdio.h>
#include <graphics.h>
#define OFF 0
#define ON  1
#define isvalid(x,y) ((x>-1) && (x<8) && (y>-1) && (y<8))
#define PLAYER1 0
#define PLAYER2 1
#define BLACK 0
#define WHITE 1
#define SPACE 2
#define X(0)
#define X(k)   (X(k-1) + STEP)
#define Y(0)
#define Y(k)   (Y(k-1) + STEP)
void change(int x, int y, const int m, const int n);
int cboard[8][8];
int color1, color2;
static int i, j;
int player;
main()
{
 init();
 while(1) {
  drawc();
  rmvp(i, j);
  if (player == PLAYER1)
   player = PLAYER2;
  else
   player = PLAYER1;
  key = bioskey();
  switch (key) {
   case W:
    if (isvalid(i, --j)
     mvp(X(i), Y(j);
    else {
     ++j;
     continue;
    }
    break;
   case S:  if (isvalid(i, ++j)
     mvp(X(i), Y(j);
    else {
     --j;
     continue;
    }
    break;
   case A: if (isvalid(--i, j)
     mvp(X(i), Y(j);
    else {
     ++i;
     continue;
    }
    break;
   case D: if (isvalid(++i, j)
     mvp(X(i), Y(j);
    else {
     --i;
     continue;
    }
    break;
   case ESC: exit();
   default:
    mvp(i, j);
    continue;
  }
  if ((check(i, j, player))
   continue;
  if (end())
   exit();
 }
 drawscore();
}

int check(int x, int y, int player)
{
 if (!isvalid(x,y))
  return 0;
 if (cboard[x][y] != SPACE)
  return 0;

 if (player == PLAYER1)
  color1 = BLACK, color2 = WHITE;
 else
  color1 = WHITE, color2 = BLACK;

 change(x, y, 0, 1);
 change(x, y, 0, -1);
 change(x, y, 1, 0);
 change(x, y, -1, 0);
 change(x, y, 1, 1);
 change(x, y, -1, -1);
 change(x, y, 1, -1);
 change(x, y, -1, 1);

 return 1;
}

/* ............*/
void change(int x, int y, const int m, const int n)
{
 int hx, hy;
 int state;

 state = OFF;
 for (hx = x+m, hy = y+n; isvalid(hx,hy); hx+=m, hy+=n)
  if (cboard[hx][hy] == color2) {
   state = ON;
   continue;
  } else if (cboard[hx][hy] == color1)
   break;
  else {
   state = OFF;
   break;
  }
 if (state == ON) {
  for ( ; hx != x && hy != y; hx-=m, hy-=n)
   cboard[hx][hy] = color1;
  cboard[hx][hy] = color1;
 }
}