www.pudn.com > PocketC.zip > TicTac.c

// Tic-Tac-Toe 
int brd[9]; // The board 
 
drawx(int x, int y) { 
   // Draw an 'x' at grid location (x,y) 
   x = x * 40 + 20; 
   y = y * 40 + 27; 
   line(1, x+3, y+3, x+37, y+37); 
   line(1, x+3, y+37, x+37, y+3); 
} 
 
drawo(int x, int y) { 
   // Draw an 'o' at grid location (x,y) 
   x = x * 40 + 20; 
   y = y * 40 + 27; 
   frame(1, x+3, y+3, x+37, y+37, 17); 
} 
 
verify(int a, int b, int c) { 
   // verify that locations a,b,c contain the same pieces 
   char chk; 
 
   chk = brd[a] + brd[b]*4 + brd[c]*16; 
   if (chk == 21 || chk == 42) return 1; 
   return 0; 
} 
 
winner() { 
   // check along each line/diagonal 
   if (verify(0,1,2)) return 1; 
   if (verify(3,4,5)) return 2; 
   if (verify(6,7,8)) return 3; 
   if (verify(0,3,6)) return 4; 
   if (verify(1,4,7)) return 5; 
   if (verify(2,5,8)) return 6; 
   if (verify(0,4,8)) return 7; 
   if (verify(2,4,6)) return 8; 
   return 0; 
} 
 
human() { 
   int x, y; 
   while(1) { 
      // Wait for a pen up event 
      waitp(); 
      x = penx(); 
      y = peny(); 
      // Did the user tap outside the grid? 
      if (x<20 || x>140 || y<27 || y>147) 
         return -1; 
 
      // Get grid coordinates 
      x = (x-20)/40; 
      y = (y-27)/40; 
 
      if (brd[x+3*y] == 0) { 
         // mark the space as used 
         brd[x+3*y] = 1; 
         drawx(x,y); 
         if (winner()) return 1; 
         else return 0; 
      } 
   } 
} 
 
#ifndef DUMB 
// "AI" provided by Thaddaeus Frogley  
cpu() { 
  int loc; 
  int a,b,c; 
 
  loc=-1; 
  b=1; 
  c=0; 
  for(a=0;a<9;a++){ 
    if ( brd[a]==0){ 
 
      if (loc==-1){ 
        loc=a; 
      } 
      else if (c==0 && (random(b)==0 || a==4)){ 
        loc=a; 
        b++; 
        if (a==4) c=1; 
      } 
 
      brd[a] = 2; 
      if (winner()){ 
        loc=a; 
        break; 
      } 
      else{ 
        brd[a] = 1; 
        if (winner()){  
          loc=a; 
          c=1; 
        } 
      } 
      brd[a] =0; 
 
    } 
  } 
 
  drawo(loc%3, loc/3); 
  brd[loc] = 2; 
 
   if (winner()) return 1; 
   else return 0; 
} 
#else 
 
cpu() { 
   int loc; 
 
   // Find an empty space 
   do { 
      loc = random(9); 
   } while (brd[loc] != 0); 
 
   drawo(loc%3, loc/3); 
   brd[loc] = 2; 
 
   if (winner()) return 1; 
   else return 0; 
} 
#endif 
 
main() { 
   int numMoves, win; 
 
   numMoves = win = 0; 
   clear(); 
   puts("Tic-Tac-Toe: A PocketC demo\n\nTap outside the grid to exit.\nTap anywhere to start...\n"); 
   wait(); 
   graph_on(); 
   title("Tic-Tac-Toe"); 
 
   // Draw the board 
   line(1,60,27,60,147); 
   line(1,100,27,100,147); 
   line(1,20,67,140,67); 
   line(1,20,107,140,107); 
 
   // Draw the gray border 
   frame(2, 20, 27, 140, 147, 0); 
 
   while (1) { 
      // we are done when either the human or the cpu wins 
      // or when the board is full 
      win=human(); 
      if (win==-1) return; // Exit 
      if (win) { 
         text(56,82,"Human wins!"); 
         break; 
      } 
      numMoves++; 
      if (numMoves>8) { 
         text(68,82,"Draw!"); 
         break; 
      } 
      if (cpu()) { 
         text(51,82,"PalmPilot wins!"); 
         break; 
      } 
      numMoves++; 
   } 
   wait(); 
}