#include<bits/stdc++.h> using namespace std; int n,m,sx,sy,ans=1; char a[21][21]; int fx[4]={0,1,0,-1}; int fy[4]={1,0,-1,0}; void dfs(int x,int y){ a[x][y]='#'; for(int i=0;i<=3;i++){ int tx=x+fx[i]; int ty=y+fy[i]; if(tx>=1&&tx<=n&&ty>=1&&ty<=m&&a[tx][ty]!='#'){ ans++; dfs(tx,ty); } } } int main(){ cin>>m>>n; for(int i=1;i<=n;i++){ for(int j=1;j<=m;j++){ cin>>a[i][j]; if(a[i][j]=='@'){ sx=i; sy=j; } } } dfs(sx,sy); cout<<ans; return 0; } /************************************************************** Problem: 1897 User: linyifan Language: C++ Result: Accepted Time:21 ms Memory:2072 kb ****************************************************************/