#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
typedef long long int ll;
typedef long double ld;
#define FOR(i,l,r) for(ll i=l;i<r;i++)
#define REP(i,n) FOR(i,0,n)
#define RFOR(i,l,r) for(ll i=r-1;i>=l;i--)
#define RREP(i,n) RFOR(i,0,n)
#define ALL(x) x.begin(),x.end()
#define P pair<ll,ll>
#define F first
#define S second
#define BS(A,x) binary_search(ALL(A),x)
#define LB(A,x) (ll)(lower_bound(ALL(A),x)-A.begin())
#define UB(A,x) (ll)(upper_bound(ALL(A),x)-A.begin())
#define COU(A,x) UB(A,x)-LB(A,x)
template<typename T>using min_priority_queue=priority_queue<T,vector<T>,greater<T>>;
using mint=modint1000000007;
signed main(){
  ll N,K,ans=0;cin>>N>>K;vector<ll>A(N),M(N),DP(N+1,-1e18);
  vector<vector<ll>>B(N,vector<ll>());
  REP(i,N){cin>>A[i]>>M[i];REP(j,M[i]){ll b;cin>>b;B[i].push_back(b);}}DP[0]=0;
  REP(i,N){
    REP(j,M[i])DP[0]=max(DP[0],DP[B[i][j]]+A[i]);DP[i+1]=max(DP[i+1],DP[0]-A[i]);
  }
  REP(i,N+1)ans=max(ans,DP[i]);cout<<ans<<endl;
  return 0;
}