HDU 4101 Ali and Baba

两次广搜

#include<cstdio>
#include<cstring>
#include<cmath>
#include<queue>
#include<algorithm>
using namespace std;

const int maxn=305;
int N,M,Sx,Sy;
int Map[maxn][maxn];
int Y[maxn][maxn];
int e[maxn][maxn];
int flag[maxn][maxn];
int Flag[maxn][maxn];
int F[maxn][maxn];
int dir[4][2]={{-1,0},{1,0},{0,-1},{0,1}};
int ans,sum;


struct Point
{
    int x,y;
    Point(int a,int b){x=a;y=b;}
};
void init()
{
    memset(flag,0,sizeof flag);//标记有没有走过
    memset(F,0,sizeof F);//标记是否是边界
    memset(Map,0,sizeof Map);
    memset(Flag,0,sizeof Flag);
    memset(e,0,sizeof e);
    memset(Y,0,sizeof Y);
    ans=-1,sum=0;
}

void read()
{
    for(int i=1;i<=N;i++)
        for(int j=1;j<=M;j++)
        {
            scanf("%d",&Map[i][j]);
            Y[i][j]=Map[i][j];
        }
}

void bfs1()
{
    queue<Point>Q;
    Point p(Sx,Sy);
    flag[Sx][Sy]=1;
    Q.push(p);
    while(!Q.empty())
    {
        Point p=Q.front(); Q.pop();
        
        if(Map[p.x][p.y]!=0&&Map[p.x][p.y]!=-1)
        {
            F[p.x][p.y]=1;//边界标1
            continue;
        }

        for(int i=0;i<4;i++)
        {
            int NewX=p.x+dir[i][0];
            int NewY=p.y+dir[i][1];
            if(!flag[NewX][NewY])
                if(NewX>=1&&NewX<=N)
                    if(NewY>=1&&NewY<=M)
                    {
                        flag[p.x][p.y]=1;
                        Point p(NewX,NewY);
                        Q.push(p);
                    }
        }
    }
    /*
    for(int i=1;i<=N;i++)
    {
        for(int j=1;j<=M;j++)
            printf("%d",F[i][j]);
        printf("
");
    }
    */
}

void bfs2()
{
    queue<Point>Q;
    Point p(0,0);
    Flag[0][0]=1;
    Q.push(p);
    while(!Q.empty())
    {
        Point p=Q.front(); Q.pop();
        //printf("%d  %d  %d
",p.x,p.y,Map[p.x][p.y]);
        
        if(Map[p.x][p.y])
        {
            if(F[p.x][p.y]) 
            {
                sum=sum+Map[p.x][p.y]-1;
                continue;
            }
            else sum=sum+Map[p.x][p.y];
        }

        for(int i=0;i<4;i++)
        {
            int NewX=p.x+dir[i][0];
            int NewY=p.y+dir[i][1];
            if(Flag[NewX][NewY]==0)
                if(NewX>=0&&NewX<=N+1)
                    if(NewY>=0&&NewY<=M+1)
                    {
                        Flag[NewX][NewY]=1;
                        Point p(NewX,NewY);
                        Q.push(p);
                    }
        }
    }

}

void dfs(int x,int y)
{
    if(x==0||x==N+1||y==0||y==M+1) {ans=1;return;}
    e[x][y]=1;
    for(int i=0;i<4;i++)
    {
        int NewX=x+dir[i][0];
        int NewY=y+dir[i][1];
        if(Y[NewX][NewY]==0)
            if(e[NewX][NewY]==0)
                dfs(NewX,NewY);
    }
}

void solve()
{
    for(int i=1;i<=N;i++)
        for(int j=1;j<=M;j++)
            if(Map[i][j]==-1)
                Sx=i,Sy=j;
    e[Sx][Sy]=1;dfs(Sx,Sy);
    if(ans==1){printf("Ali Win
");return;}
    bfs1();
    bfs2();
  //  printf("%d
",sum);
    if(sum%2==1) printf("Ali Win
");
    else printf("Baba Win
");
}

int main()
{
    while(~scanf("%d%d",&N,&M))
    {
        init();
        read();
        solve();
    }
    return 0;
}