#include<iostream>#include<cstdio>#include<queue>#include <cstring>using namespace std;int N,a[35][35];char A[35][35];typedef struct stq{int x,y;}stq;queue <stq> Q;int m[4][2]={{0,1},{0,-1},{1,0},{-1,0}};void BFS(int x, int y);int main(){int i,j,c;while(scanf("%d",&N)!=EOF){for(i=0;i<=N+1;i++) for(j=0;j<=N+1;j++) a[i][j]=0;for(i=1;i<=N;i++) scanf("%s",A[i]+1);BFS(1,1);BFS(N,N);c=0; for(i=1;i<=N;i++) for(j=1;j<=N;j++) { if(a[i][j]==1) { if(a[i-1][j]==0)c++; if(a[i+1][j]==0)c++; if(a[i][j-1]==0)c++; if(a[i][j+1]==0)c++; } }printf("%dn",(c-4)*9); }return 0;}void BFS(int aa,int b){int i,j; stq sq,q;sq.x=aa; sq.y=b;a[sq.x][sq.y]=1;Q.push(sq);while(!Q.empty()){q=Q.front();Q.pop();for(i=0;i<4;i++){sq.x= q.x+m[i][0];sq.y=q.y+m[i][1]; if(sq.x>N||sq.x<1|| sq.y>N||sq.y<1 ||A[sq.x][sq.y]=='#'||a[sq.x][sq.y]==1) continue; a[sq.x][sq.y]=1; Q.push(sq);}}}
