#include<iostream>

#include<cstdio>

#include<cmath>

#include<cstdlib>

#include<cstring>

#include<algorithm>

#include<bitset>

using namespace std;

int read()

{

    int x=,f=;char c=getchar();

    while (c<''||c>'') {if (c=='-') f=-;c=getchar();}

    while (c>=''&&c<='') x=(x<<)+(x<<)+(c^),c=getchar();

    return x*f;

}

#define N 2010

int n,ans=;

bitset<N> a[N];

int main()

{

    freopen("bzoj2208.in","r",stdin);

    freopen("bzoj2208.out","w",stdout);

    n=read();

    for (int i=;i<=n;i++)

    {

        char c=getchar();

        while (c!=''&&c!='') c=getchar();

        for (int j=;j<=n;j++)

        a[i][j]=c^,c=getchar();

        a[i][i]=;

    }

    for (int k=;k<=n;k++)

        for (int i=;i<=n;i++)

        if (a[i][k]) a[i]|=a[k];

    for (int i=;i<=n;i++) ans+=a[i].count();

    cout<<ans;

    fclose(stdin);fclose(stdout);

    return ;

}