白银莲花池

#include <bits/stdc++.h>

using namespace std;

#define p make_pair
#define ll long long
#define INF 0x3f3f3f3f
#define MAXN 1000010
#define MAXM 1010

inline int read()
{
    int x = 0,ff = 1;char ch = getchar();
    while(!isdigit(ch))
    {
        if(ch == '-') ff = -1;
        ch = getchar();
    }
    while(isdigit(ch))
    {
        x = (x << 1) + (x << 3) + (ch ^ 48);
        ch = getchar();
    }
    return x * ff;
}

int n,m,sx,sy,tx,ty,sum = 0,a[MAXM][MAXM],vis[MAXM][MAXM],v[MAXM][MAXM];
int dx[8] = {2,2,-2,-2,1,1,-1,-1};
int dy[8] = {1,-1,1,-1,2,-2,2,-2};
ll f[MAXM][MAXM],dis[MAXM][MAXM],d[MAXM][MAXM];

void BFS()
{
    memset(dis,0x3f,sizeof(dis));
    memset(vis,false,sizeof(vis));
    queue < pair < int , int > > q;
    q.push(p(sx,sy)); dis[sx][sy] = 0; vis[sx][sy] = true;
    while(!q.empty())
    {
        int x = q.front().first;
        int y = q.front().second;
        q.pop();
        vis[x][y] = false;
//        printf("x = %d y = %d
",x,y);
        for(int i = 0;i <= 7;++i)
        {
            int xx = x + dx[i];
            int yy = y + dy[i];
            if(xx < 1 || xx > n || yy < 1 || yy > m || a[xx][yy] == 2) continue;
            if(dis[xx][yy] > dis[x][y] + v[xx][yy])
            {
                dis[xx][yy] = dis[x][y] + v[xx][yy];
//            printf("xx = %d yy = %d
",xx,yy);
                if(xx == tx && yy == ty) continue;
                if(!vis[xx][yy]) 
                {
                    vis[xx][yy] = true;
                    q.push(p(xx,yy));
                }
            }
        }
    }
    
}

void BFS2()
{
    memset(d,0x3f,sizeof(d));
    memset(vis,false,sizeof(vis));
    queue < pair < int , int > > q;
    q.push(p(sx,sy)); d[sx][sy] = 0; vis[sx][sy] = true;
    while(!q.empty())
    {
        int x = q.front().first;
        int y = q.front().second;
        q.pop();
        vis[x][y] = false;
//        printf("x = %d y = %d
",x,y);
        for(int i = 0;i <= 7;++i)
        {
            int xx = x + dx[i];
            int yy = y + dy[i];
            if(xx < 1 || xx > n || yy < 1 || yy > m || a[xx][yy] == 2) continue;
            if(dis[xx][yy] != dis[x][y] + v[xx][yy]) continue;
            if(d[xx][yy] > d[x][y] + 1)
            {
                d[xx][yy] = d[x][y] + 1;
//            printf("xx = %d yy = %d
",xx,yy);
                if(xx == tx && yy == ty) continue;
                if(!vis[xx][yy]) 
                {
                    vis[xx][yy] = true;
                    q.push(p(xx,yy));
                }
            }
            
        }
    }
    
}

void BFS3()
{
    memset(vis,false,sizeof(vis));
    queue < pair < int , int > > q;
    q.push(p(sx,sy)); vis[sx][sy] = true; f[sx][sy] = 1;
    while(!q.empty())
    {
        int x = q.front().first;
        int y = q.front().second;
        q.pop();
        vis[x][y] = false;
        for(int i = 0;i <= 7;++i)
        {
            int xx = x + dx[i];
            int yy = y + dy[i];
            if(xx < 1 || xx > n || yy < 1 || yy > m || a[xx][yy] == 2) continue;
            if(dis[xx][yy] != dis[x][y] + v[xx][yy]) continue;
            if(d[xx][yy] != d[x][y] + 1) continue;
            f[xx][yy] += f[x][y];
            if(xx == tx && yy == ty) continue; 
            if(!vis[xx][yy]) 
            {
                vis[xx][yy] = true;
                q.push(p(xx,yy));
            }    
        }
    }
}

int main()
{
    n = read(); m = read();
    for(int i = 1;i <= n;++i)
    {
        for(int j = 1;j <= m;++j)
        {
            a[i][j] = read();
            if(a[i][j] == 3) { sx = i; sy = j; v[i][j] = 0;}
            if(a[i][j] == 4) { tx = i; ty = j; v[i][j] = 0;}
            if(a[i][j] == 0) v[i][j] = 1;
            if(a[i][j] == 1) v[i][j] = 0;
        }
    }
    BFS();
    if(dis[tx][ty] == dis[0][0]) { printf("-1
"); return 0; }
    printf("%lld
",dis[tx][ty]);
    BFS2();
    printf("%lld
",d[tx][ty]);
    BFS3();
    printf("%lld
",f[tx][ty]);
    return 0;
}