UVa 639

#include<bits/stdc++.h>
using namespace std;

typedef long long int           ll;
typedef unsigned long long int  ull;
typedef vector<int>             vi;
typedef vector<vi>              vvi;
typedef pair<int,int>           pii;
typedef vector< pii >           vpii;
typedef set<int>                sti;

#define pb                      push_back
#define pob                     pop_back
#define mp                      make_pair
#define ff                      first
#define ss                      second
#define loop1(i,n)              for(int i=1; i<=int(n); i++)
#define loop(i,y)               for(int i=0; i<int(y); i++)
#define rloop(i,y)              for(int i=int(y)-1; i>=0; i--)
#define read()                  freopen("input.txt", "r", stdin)
#define write()                 freopen("output.txt", "w", stdout)
#define cspf(i)                 printf("Case %d:\n", i)
/// Constants
#define eps                     1e-9
#define PI                      acos(-1.0)  // 3.1415926535897932

int main()
{
    read();
    int n;
    while(1){
        scanf("%d",&n);
        if(n==0)
            break;
        char a[110][110];
        loop(i,n){
            scanf("%s",a[i]);
        }
        int cnt=0,check[110][110];
        loop(i,n){
            loop(j,n){
                check[i][j]=0;
            }
        }
        loop(i,n){
            loop(j,n){
                if(a[i][j]=='X' || check[i][j]==1)
                    continue;
                int r=0,c=0;
                for(int k=0;k<j;k++){
                    if(check[i][k]!=0)
                        r=1;
                    if(r==1 && a[i][k]=='X')
                        r=0;
                }
                for(int k=0;k<i;k++){
                    if(check[k][j]!=0)
                        c=1;
                    if(c==1 && a[k][j]=='X')
                        c=0;
                }
                if(r==0 && c==0){
                    cnt++;
                    if(a[i+1][j+1]=='X' && a[i][j+1]=='.')
                        check[i][j+1]=1;
                    else
                        check[i][j]=1;
                }
            }
        }
        loop(i,n){
            loop(j,n){
               // printf("%d ",check[i][j]);
            }
            //printf("\n");
        }
        printf("%d\n",cnt);
    }
    return 0;
}