2806 红与黑

#include<bits/stdc++.h>
using namespace std;
int f[25][25];
char a[25][25];
int w,h;
int F(int i,int j){
    if(a[i][j]==‘#‘)return f[i][j]=0;
    if(f[i][j])return 0;
    if(i<1||i>h)return f[i][j]=0;
    if(j>w||j<1)return f[i][j]=0;
    f[i][j]++;

    return f[i][j]+=F(i-1,j)+F(i+1,j)+F(i,j+1)+F(i,j-1);
    
}
int main(){
    
    while(cin>>w>>h){
        if(!w&&!h)break;
        for(int i=1;i<=25;i++)
        for(int j=1;j<=25;j++)f[i][j]=0;
        int x,y;
        for(int i=1;i<=h;i++)
        for(int j=1;j<=w;j++){
            cin>>a[i][j];
            if(a[i][j]==‘@‘){
                x=i;y=j;
            }
        }
        
        cout<<F(x,y)<<endl;
        
    }
}