【NOIP 2011】 Mayan游戏

【题目链接】

https://www.luogu.org/problemnew/show/P1312

【算法】

深度优先搜索

【代码】

#include<bits/stdc++.h>
using namespace std;

struct info
{
        int x,y,op;
} step[];

int i,n,t,x;
int a[][];
bool solved;

inline void print()
{
        int i;
        for (i = ; i <= n; i++) printf("%d %d %d\n",step[i].x - ,step[i].y - ,step[i].op);
}
inline bool check()
{
        int i;
        for (i = ; i <= ; i++)
        {
                if (a[i][] != )
                        return false;
        }
        return true;
}
inline bool Remove()
{
        int i,j,x,y,t;
        bool ret = false;
        bool d[][];
        memset(d,false,sizeof(d));
        for (i = ; i <= ; i++)
        {
                for (j = ; j <= ; j++)
                {
                        if (a[i][j])
                        {
                                for (x = j + ; a[i][j] == a[i][x] && x <= ; x++);
                                if (x - j >= )
                                {
                                        for (y = j; y < x; y++)
                                                d[i][y] = true;
                                        ret = true;
                                }
                                for (x = i + ; a[i][j] == a[x][j] && x <= ; x++);
                                if (x - i >= )
                                {
                                        for (y = i; y < x; y++)
                                                d[y][j] = true;
                                        ret = true;
                                }
                        }
                }
        }
        for (i = ; i <= ; i++)
        {
                for (j = ; j <= ; j++)
                {
                        if (d[i][j])
                                a[i][j] = ;
                }
        }
        for (i = ; i <= ; i++)
        {
                t = ;
                for (j = ; j <= ; j++)
                {
                        if (!a[i][j])
                        {
                                for (x = j + ; x <=  && !a[i][x]; x++);
                                a[i][j] = a[i][x];
                                a[i][x] = ;
                        }
                }
        }
        return ret;
}

inline void dfs(int dep)
{
        int i,j,x,y;
        int b[][];
        if (dep > n)
        {
                if (check())
                {
                        solved = true;
                        print();
                }
                return;
        }
        for (i = ; i <= ; i++)
        {
                for (j = ; j <= ; j++)
                {
                        b[i][j] = a[i][j];
                }
        }
        for (i = ; i <= ; i++)
        {
                for (j = ; j <= ; j++)
                {
                        if (i <  && a[i][j] != )
                        {
                                if (a[i+][j] != )
                                {
                                        step[dep] = (info){i,j,};
                                        swap(a[i][j],a[i+][j]);
                                        while (Remove());
                                        dfs(dep+);
                                        if (solved) return;
                                        for (x = ; x <= ; x++)
                                        {
                                                for (y = ; y <= ; y++)
                                                {
                                                        a[x][y] = b[x][y];
                                                }
                                        }
                                } else
                                {
                                        step[dep] = (info){i,j,};
                                        for (x = j - ; x >=  && !a[i+][x]; x--);
                                        a[i+][x+] = a[i][j];
                                        for (x = j; x <= ; x++) a[i][x] = a[i][x+];
                                        while (Remove());
                                        dfs(dep+);
                                        if (solved) return;
                                        for (x = ; x <= ; x++)
                                        {
                                                for (y = ; y <= ; y++)
                                                {
                                                        a[x][y] = b[x][y];
                                                }
                                        }
                                }
                        }
                        if (i >  && a[i][j] != )
                        {
                                if (a[i-][j] == )
                                {
                                        step[dep] = (info){i,j,-};
                                        for (x = j - ; x >=  && !a[i-][x]; x--);
                                        a[i-][x+] = a[i][j];
                                        for (x = j; x <= ; x++) a[i][x] = a[i][x+];
                                        while (Remove());
                                        dfs(dep+);
                                        if (solved) return;
                                        for (x = ; x <= ; x++)
                                        {
                                                for (y = ; y <= ; y++)
                                                {
                                                        a[x][y] = b[x][y];
                                                }
                                        }
                                }
                        }
                }
        }
}

int main()
{

        scanf("%d",&n);
        for (i = ; i <= ; i++)
        {
                t = ;
                while (scanf("%d",&x) && x)
                        a[i][++t] = x;
        }
        solved = false;
        dfs();
        if (!solved) printf("-1\n");

        return ;

}