#include<iostream>

#include<algorithm>

#include<cmath>

#include<cstring>

#include<cstdio>

#include<vector>

#include<queue>

#include<stack>

#include<bitset>

#include<map>

using namespace std;

struct EDGE{

    int ed,nex;

}edge[],edgec[];

int num,numc,ans,first[],firstc[];

int n,ord,sccnum,top;

int sta[],dfn[],low[],bl[],du[];

char ch[];

bool ins[];

vector<int>scc[];

bitset<>s[];

void add(int st,int ed){

//    cout<<"st="<<st<<" ed="<<ed<<endl;

    edge[++num].ed=ed;

    edge[num].nex=first[st];

    first[st]=num;

}

void addc(int st,int ed){

//    cout<<"Stc="<<st<<" edc="<<ed<<endl;

    edgec[++numc].ed=ed;

    edgec[numc].nex=firstc[st];

    firstc[st]=numc;

}

void tarjan(int x){

    dfn[x]=low[x]=++ord;

    sta[++top]=x;ins[x]=;

    for(int i=first[x];i;i=edge[i].nex){

        int y=edge[i].ed;

        if(!dfn[y]){

            tarjan(y);

            low[x]=min(low[x],low[y]);

        }else if(ins[y])

            low[x]=min(low[x],dfn[y]);

    }if(dfn[x]==low[x]){

        sccnum++;int p;

        do{

            p=sta[top--];ins[p]=;

            bl[p]=sccnum;scc[sccnum].push_back(p);

        }while(p!=x);

    }

}

void topsort(){

    queue<int>q;

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

        if(du[i]==) q.push(i);

    while(!q.empty()){

        int x=q.front();q.pop();

    //    cout<<x<<" ";

        for(int i=firstc[x];i;i=edgec[i].nex){

            int y=edgec[i].ed;

            du[y]--;

            s[y]|=s[x];

            if(du[y]==)

                q.push(y);

        }

    }

}

int main(){

//    freopen("a,in","r",stdin);

    scanf("%d",&n);

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

        scanf("%s",ch+);

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

            if(ch[j]-'')

                add(i,j);

    }

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

        if(!dfn[i]) tarjan(i);

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

        for(int j=first[i];j;j=edge[j].nex){

            int y=edge[j].ed;

            if(bl[i]==bl[y]) continue;

            addc(bl[i],bl[y]);

            du[bl[y]]++;

        }

    for(int i=;i<=sccnum;i++){

        for(int j=;j<scc[i].size();j++){

            int y=scc[i][j];

            s[i][y]=;

        }

    }

    topsort();

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

        ans+=s[i].count()*scc[i].size();

    printf("%d\n",ans);

    return ;

}