#include <iostream>
#include <cstdio>
#include <ctime>
using namespace std;

const int X = 8, Y = 8;

int chess[X][Y];

bool nextxy(int &x, int &y, int count)
{
    switch(count){
case 0:
    if(x+1 < X && y-2 >= 0 && !chess[x+1][y-2]){
        x  = x+1, y = y-2;
        return true;
    }
    break;
case 1:
    if(x+2 < X && y-1 >= 0 && !chess[x+2][y-1]){
        x = x+2, y = y-1;
        return true;
    }
    break;
case 2:
    if(x+2 < X && y+1 < Y  && !chess[x+2][y+1]){
        x = x+2, y = y+1;
        return true;
    }
    break;
case 3:
    if(x+1 < X && y+2 < Y && !chess[x+1][y+2]){
        x = x+1, y = y+2;
        return true;
    }
    break;
case 4:
    if(x-1 >= 0 && y+2 < Y && !chess[x-1][y+2]){
        x = x-1, y = y+2;
        return true;
    }
    break;
case 5:
    if(x-2 >= 0 && y+1 < Y && !chess[x-2][y+1]){
        x = x-2, y =y+1;
        return true;
    }
    break;
case 6:
    if(x-2 >= 0 && y-1 >= 0 && !chess[x-2][y-1]){
        x = x-2, y = y-1;
        return true;
    }
    break;
case 7:
    if(x-1 >= 0 && y-2 >= 0 && !chess[x-1][y-2]){
        x = x-1, y = y-2;
        return true;
    }
    break;
    }
return false;
}

void outputChess()
{
    int i, j;
    for(i = 0; i < X; i++){
        for(j = 0;j < Y; j++)
            printf("%-4d", chess[i][j]);
        cout<<endl;
        }
    cout<<endl;
}

bool knightTour(int x, int y, int tag = 1)
{
    chess[x][y] = tag;
    int count = 0, x1 = x, y1 = y;
    bool flag = false;

    if(X*Y == tag){
        outputChess();
        return true;
    }

    while(count < 8){
        flag = false;
        x1 = x, y1 = y;

        while(!flag && count < 8)
            flag = nextxy(x1, y1, count++);

        if(flag && knightTour(x1, y1, tag+1))
            return true;
    }

    if(8 == count){
        chess[x][y] = 0;
        return false;
    }
}


int main()
{
    int x, y;
    clock_t start, finsh;
    cout<<"请输入骑士初始位置：";
    cin>>x>>y;

    start = clock();

    if(!knightTour(x,y))
        cout<<"ERROR\n";

    finsh = clock();
    cout<<"暴力求解所用时间为："<<(double)(finsh-start)/CLOCKS_PER_SEC<<"s\n";

}