#include
#include
#include
#include
#include
#include
using namespace std;
#define pos(i,a,b) for(int i=(a);i<=(b);i++)
#define N 2000500
int n,m;
vector son[N];
int wei[N];
int ji[N];
int ans;
bool tmp(const int &a,const int &b)
{
     return wei[a]
}
void dp(int x)
{
     if(ji[x]==0)
       return;
     pos(i,0,ji[x]-1)
     {
         dp(son[x][i]);
     }
     sort(son[x].begin(),son[x].end(),tmp);
     pos(i,0,ji[x]-1)
     {
       if(wei[x]-1+wei[son[x][i]]<=m)
       {
          ans++;
          wei[x]+=wei[son[x][i]]-1;
       }
     }

}
int main()
{
    freopen("sakura.in","r",stdin);
    freopen("sakura.out","w",stdout);
    cin>>n>>m;
    pos(i,1,n)
      scanf("%d",&wei[i]);
    pos(i,1,n)
    {
      scanf("%d",&ji[i]);
      wei[i]+=ji[i];
      pos(j,1,ji[i])
      {
          int p;
          scanf("%d",&p);
          p++;
          son[i].push_back(p);
      }
    }
    dp(1);
    cout<<ans;
    //while(1);
    return 0;
}