#include<bits/stdc++.h>

 #define N 100005

 #define LL long long

 #define inf 0x3f3f3f3f

 #define ls tr[x][0]

 #define rs tr[x][1]

 using namespace std;

 inline int ra()

 {

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

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

     while (ch>='' && ch<='') {x=x*+ch-''; ch=getchar();}

     return x*f;

 }

 struct node{

     int c,v,from,to,next;

 }e[N];

 int tot=,ans,from[N],n,m,S,T,head[N],cnt,dis[N],q[N<<];

 bool inq[N];

 void ine(int x, int y, int v, int c)

 {

     e[++tot].to=y; e[tot].next=head[x]; head[x]=tot;

     e[tot].v=v; e[tot].c=c; e[tot].from=x;

 }

 void insert(int x, int y, int c, int v)

 {

     ine(x,y,v,c); ine(y,x,-v,);

 }

 bool spfa()

 {

     for (int i=; i<=n+; i++) dis[i]=inf;

     int l=,r=; q[]=S; dis[S]=; inq[S]=;

     while (l<r)

     {

         int x=q[l++];

         for (int i=head[x];i;i=e[i].next)

             if (dis[e[i].to]>dis[x]+e[i].v && e[i].c)

             {

                 dis[e[i].to]=dis[x]+e[i].v;

                 from[e[i].to]=i;

                 if (!inq[e[i].to])

                 {

                     inq[e[i].to]=;

                     q[r++]=e[i].to;

                 }

             }

         inq[x]=;

     }

     if (dis[T]==inf) return ;

     return ;

 }

 void mcf()

 {

     int x=inf;

     for (int i=from[T];i;i=from[e[i].from]) x=min(x,e[i].c);

     for (int i=from[T];i;i=from[e[i].from]) ans+=x*e[i].v,e[i].c-=x,e[i^].c+=x;

 }

 void fyl()

 {

     while (spfa()) mcf();

 }

 int main()

 {

     n=ra();

     S=n+; T=n+;

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

     {

         int cnt=ra();

         insert(i,T,cnt,);

         if (i!=) insert(i,,inf,);

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

         {

             int x=ra(),v=ra();

             insert(S,x,,v);

             insert(i,x,inf,v);

         }

     }

     fyl();

     cout<<ans;

     return ;

 }