第八章棋盘问题

#include <cstdio>
#include <iostream>
#include <algorithm>
#include <cstring>

using namespace std;

const int maxn=10000;
int board[maxn][maxn];
int k;
int cnt=1;

//左闭右闭区间
void solve(int x1,int x2,int y1,int y2,int m,int n)
{
    //cout<<x1<<" "<<x2<<" "<<y1<<" "<<y2<<endl;

    if(x2-x1==1)
    {
        for(int i=x1;i<=x2;i++)
            for(int j=y1;j<=y2;j++)
                if(board[i][j]==-1) board[i][j]=cnt;

        cnt++;

        return;
    }

    int mx=x1+(x2-x1)/2;
    int my=y1+(y2-y1)/2;

    if(m<=mx && n<=my)
    {
        board[mx+1][my]=board[mx][my+1]=board[mx+1][my+1]=cnt++;

        solve(x1,mx,y1,my,m,n);
        solve(mx+1,x2,my+1,y2,mx+1,my+1);
        solve(x1,mx,my+1,y2,mx,my+1);
        solve(mx+1,x2,y1,my,mx+1,my);
    }

    if(m>mx && n<=my)
    {
        board[mx][my]=board[mx][my+1]=board[mx+1][my+1]=cnt++;

        solve(x1,mx,y1,my,mx,my);
        solve(mx+1,x2,my+1,y2,mx+1,my+1);
        solve(x1,mx,my+1,y2,mx,my+1);
        solve(mx+1,x2,y1,my,m,n);
    }

    if(m<=mx && n>my)
    {
        board[mx+1][my]=board[mx][my]=board[mx+1][my+1]=cnt++;

        solve(x1,mx,y1,my,mx,my);
        solve(mx+1,x2,my+1,y2,mx+1,my+1);
        solve(x1,mx,my+1,y2,m,n);
        solve(mx+1,x2,y1,my,mx+1,my);
    }

    if(m>mx && n>my)
    {
        board[mx+1][my]=board[mx][my]=board[mx][my+1]=cnt++;

        solve(x1,mx,y1,my,mx,my);
        solve(mx+1,x2,my+1,y2,m,n);
        solve(x1,mx,my+1,y2,mx,my+1);
        solve(mx+1,x2,y1,my,mx+1,my);
    }

}

void print_board()
{
    for(int i=0;i<(1<<k);i++) 
    {
        for(int j=0;j<(1<<k);j++) printf("%3d ",board[i][j]);
        printf("
");
    }
}

int main()
{
    memset(board,-1,sizeof(board));
    cin>>k;
    int m,n;
    cin>>m>>n;

    board[m][n]=0;

    solve(0,(1<<k)-1,0,(1<<k)-1,m,n);

    print_board();

    return 0;
}

注意m,n的改变和起始位置和终止位置的改变