#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
#define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
#define ll long long
#define FASTIO ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define inf 1e18
#define ff first
#define ss second
#define lb lower_bound
#define ub upper_bound
#define bs binary_search
#define mod 1000000007
#define pb push_back
#define all(s) s.begin(),s.end()
#define pie 3.14159265358979323846
#define fr(i,a,b)  for(ll i=a;i<b;i++)
#define frr(i,a,b) for(ll i=b-1;i>=a;i--)
#define gcd __gcd
#define con continue
#define pii pair<ll,ll>
signed main(){
    FASTIO;
    ll tt=1;
    //cin>>tt;
    while(tt--){
         ll n;cin>>n;
         ll arr[n],sum=0;
         ll a[n],s=0;
         for(ll i=0;i<n;i++)cin>>a[i];
         for(ll i=n-1;i>=0;i--)s+=a[i],arr[i]=s,s%=mod;
         //for(ll i=0;i<n;i++)cout<<arr[i]<<" ";
         //cout<<"\n";
         for(ll i=0;i+1<n;i++){
            sum=(sum%mod+(a[i]%mod*arr[i+1]%mod)%mod)%mod;
         }
         cout<<sum%mod<<"\n";
    }
}

#include <iostream>
#include <vector>
#include <queue>
#define to first
#define cost second
const int inf=1e9+7;
using namespace std;
int main(){

  int n,tmp,r=0,flag[100]={},v=0;
  cin>>n;
  vector <pair<int,int> > gl[n];
  priority_queue <pair<int,int> ,vector<pair<int,int> >, greater<pair<int,int> > >q;
  //for(int i=1;i<n;i++) mincost[i]=inf;                                                                                                                                                       

  for(int i=0;i<n;i++) for(int j=0;j<n&&cin>>tmp;j++) if(tmp!=-1) gl[i].push_back(make_pair(j,tmp));
  int now=0;
  for(int j=0;j<n-1;j++){
    for(int i=0;i<gl[now].size();i++) if(!flag[gl[now][i].to]) q.push(make_pair(gl[now][i].cost,gl[now][i].to));
    flag[now]=1;
    for(;flag[q.top().second];) q.pop();
    //if(q.empty()) break;                                                                                                                                                                     
    r+=q.top().first;
    now=q.top().second;
    q.pop();
  }
  cout<<r<<endl;
  return 0;

}