棋盘覆盖问题

/**
    棋盘覆盖问题
    伪代码：
        chessBoard(int tr,int tc,int dr, int dc,int size)
        {
            if(size == 1) return;

            int s = size/2;
            int t = tile++;


            if (dr,dc) in top left then chessBoard(tr,tc,dr,dc,s)
            else board[tr+s-1][tc+s-1] = t
                chessBoard(tr,tc,tr+s-1,tc+s-1,s);

            if (dr,dc) in top right then chessBoard(tr,tc+s,dr,dc,s)
            else board[tr+s-1][tc+s] = t
                chessBoard(tr,tc+s,tr+s-1,tc+s,s)

            if (dr,dc) in bottom left then chessBoard(tr+s,tc,dr,dc,s)
            else board[tr+s][tr+s-1] = t
                chessBoard(tr+s,tc,tr+s,tr+s-1,s)

            if (dr,dc) in bottom right then chessBoard(tr+s,tc+s,dr,dc,s)
            else board[tr+s][tc+s] = t
                chessBoard(tr+s,tc+s,tr+s,tc+s,s)

        }
*/

#include<cstdio>
#include<cstring>

int board[9][9];
int tile = 2;
void init_board();
void display_board();
void chessBoard(int tr,int tc,int dr,int dc,int size);

int main()
{
    printf("Before cover the chessBoard: \n");
    init_board();
    display_board();
    chessBoard(1,1,3,7,8);
    printf("\nAfter cover the chessBoard: \n");
    display_board();
    return 0;
}

void init_board()
{
    memset(board,0,sizeof(board));
    board[3][7] = 1;

}

void display_board()
{
    for(int i=1;i<=8;i++){
        for(int j=1;j<=8;j++){
            printf("%3d ",board[i][j]);
        }
        printf("\n\n");
    }
}

void chessBoard(int tr,int tc,int dr,int dc,int size)
{
   if(size==1) return;

   int t = tile++;
   int s = size/2;

   //如果特殊方格在左上角子棋盘，那么覆盖左上角
   if(dr<tr+s && dc<tc+s)
        chessBoard(tr,tc,dr,dc,s);
   else{
        //如果不在，那么填充左上角子棋盘的右下角方格
        board[tr+s-1][tc+s-1] = t;
        //填充覆盖子棋盘
        chessBoard(tr,tc,tr+s-1,tc+s-1,s);
   }

    //如果特殊方格在右上角子棋盘，那么覆盖右上角
   if(dr<tr+s && dc>=tc+s)
        chessBoard(tr,tc+s,dr,dc,s);
   else{
        //如果不在，那么填充右上角子棋盘的左下角方格
        board[tr+s-1][tc+s] = t;
        //填充覆盖子棋盘
        chessBoard(tr,tc+s,tr+s-1,tc+s,s);
   }

   //如果特殊方格在左下角子棋盘，那么覆盖左下角
   if(dr>=tr+s && dc<tc+s)
        chessBoard(tr+s,tc,dr,dc,s);
   else{
        //如果不在，那么填充左下角子棋盘的右上角方格
        board[tr+s][tc+s-1] = t;
        //填充覆盖子棋盘
        chessBoard(tr+s,tc,tr+s,tc+s-1,s);
   }

    //如果特殊方格在右下角子棋盘，那么覆盖左上角
   if(dr>=tr+s && dc>=tc+s)
        chessBoard(tr+s,tc+s,dr,dc,s);
   else{
        //如果不在，那么填充右下角子棋盘的左上角方格
        board[tr+s][tc+s] = t;
        //填充覆盖子棋盘
        chessBoard(tr+s,tc+s,tr+s,tc+s,s);
   }
}