Lightoj 1012 - Guilty Prince

bfs遍历一遍就行了。

/* ***********************************************
Author        :guanjun
Created Time  :2016/6/15 18:50:31
File Name     :1012.cpp
************************************************ */
#include <iostream>
#include <cstring>
#include <cstdlib>
#include <stdio.h>
#include <algorithm>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <string>
#include <math.h>
#include <stdlib.h>
#include <iomanip>
#include <list>
#include <deque>
#include <stack>
#define ull unsigned long long
#define ll long long
#define mod 90001
#define INF 0x3f3f3f3f
#define maxn 10010
#define cle(a) memset(a,0,sizeof(a))
const ull inf = 1LL << 61;
const double eps=1e-5;
using namespace std;
priority_queue<int,vector<int>,greater<int> >pq;
struct Node{
    int x,y;
};
struct cmp{
    bool operator()(Node a,Node b){
        if(a.x==b.x) return a.y> b.y;
        return a.x>b.x;
    }
};

bool cmp(int a,int b){
    return a>b;
}
struct node{
    int x,y;
};
char mp[1100][1100];
int sx,sy;
int n,m;
int dir[4][2]={1,0,0,1,0,-1,-1,0};
int vis[1100][1100];
int bfs(){
    queue<node>q;
    cle(vis);
    node u={
        sx,sy
    };
    int ans=0;
    q.push(u);
    while(!q.empty()){
        u=q.front();
        ans++;
        q.pop();
        node v;
        for(int i=0;i<4;i++){
            v.x=u.x+dir[i][0];
            v.y=u.y+dir[i][1];
            if(v.x<=n&&v.x>=1&&v.y<=m&&v.y>=1&&mp[v.x][v.y]==‘.‘&&!vis[v.x][v.y]){
                vis[v.x][v.y]=1;
                q.push(v);
            }
        }
    }
    return ans;

}
int main()
{
    #ifndef ONLINE_JUDGE
    freopen("in.txt","r",stdin);
    #endif
    //freopen("out.txt","w",stdout);
    int T;
    cin>>T;
    for(int t=1;t<=T;t++){
        scanf("%d%d",&m,&n);
        for(int i=1;i<=n;i++){
            for(int j=1;j<=m;j++){
                cin>>mp[i][j];
                if(mp[i][j]==‘@‘)sx=i,sy=j;
            }
        }
        printf("Case %d: %d\n",t,bfs());
    }
    return 0;
}