#include<cstdio>#include<cstring>#include<algorithm>#include<queue>#include<bitset>using namespace std;const int maxn=2010,maxm=5000010;struct edge{int u,v,from;}e[maxm],e1[maxm];int n,tot,tot1,first[maxn],first1[maxn],dfn[maxn],low[maxn],mark,s[maxn],lack[maxn],color,col[maxn],num[maxn],top,in[maxn];char st[2010];bitset<maxn>f[maxn];queue<int>q;void insert(int u,int v){tot++;e[tot].u=u;e[tot].v=v;e[tot].from=first[u];first[u]=tot;}void insert1(int u,int v){tot1++;e1[tot1].u=u;e1[tot1].v=v;e1[tot1].from=first1[u];first1[u]=tot1;in[v]++;}void tarjan(int x){    dfn[x]=low[x]=++mark;    s[++top]=x;lack[x]=top;    for(int i=first[x];i;i=e[i].from)     {         int y=e[i].v;         if(!dfn[y])          {              tarjan(y);              low[x]=min(low[x],low[y]);          }         else if(!col[y])low[x]=min(low[x],dfn[y]);     }    if(dfn[x]==low[x])     {         color++;         for(int i=lack[x];i<=top;i++)col[s[i]]=color;         num[color]=top-lack[x]+1;         top=lack[x]-1;     }}int main(){    scanf("%d",&n);    for(int i=1;i<=n;i++)     {         scanf("%s",st);         for(int j=0;j<n;j++)          if(st[j]==‘1‘)insert(i,j+1);     }    for(int i=1;i<=n;i++)if(!dfn[i])tarjan(i);    for(int i=1;i<=tot;i++)     if(col[e[i].u]!=col[e[i].v])insert1(col[e[i].u],col[e[i].v]);    for(int i=1;i<=color;i++)if(!in[i])q.push(i);    for(int i=1;i<=color;i++)f[i][i]=1;    while(!q.empty())     {         int x=q.front();q.pop();         for(int i=first1[x];i;i=e1[i].from)          {              int y=e1[i].v;              f[y]|=f[x];              in[y]--;              if(in[y]==0)q.push(y);          }     }    long long ans=0;    for(int i=1;i<=color;i++)     for(int j=1;j<=color;j++)      if(f[i][j])ans+=1ll*num[i]*num[j];    printf("%lld",ans);    return 0;}