n=int(input())
e=[[] for i in range(n)]
re=[[] for i in range(n)]
for i in range(n):
  m,*t,=map(int,input().split())
  for j in range(m):
    e[i]+=[t[j]-1]
    re[t[j]-1]+=[i]
v=[0]*n
g=[0]*n
o=[]
for i in range(n):
  if v[i]==0:
    q=[i]
    while len(q)>0:
      s=q[-1]
      v[s]=1
      while g[s]<len(e[s]):
        t=e[s][g[s]]
        if v[t]==0:
          break
        g[s]+=1
      if g[s]<len(e[s]):
        q+=[t]
      else:
        o+=[s]
        q.pop()
v=[0]*n
g=[0]*n
p=[0]*n
c=0
for i in o[::-1]:
  if v[i]==0:
    s=i
    v[s]=1
    q=[s]
    for s in q:
      p[s]=c
      for t in re[s]:
        if v[t]==0:
          v[t]=1
          q+=[t]
    c+=1
E=[[] for i in range(c)]
d=[0]*c
for s in range(n):
  for t in e[s]:
    if p[s]!=p[t]:
      E[p[s]]+=[p[t]]
      d[p[t]]+=1
r=[]
q=[i for i in range(c) if d[i]==0]
for s in q:
  r+=[s]
  for t in E[s]:
    d[t]-=1
    if d[t]==0:
      q+=[t]
f=r[0]==p[0]
for i in range(c-1):
  f&=r[i+1] in E[r[i]]
print(["No","Yes"][f])