from collections import defaultdict
import sys
sys.setrecursionlimit(10 ** 6)


# n : 頂点数
# 辺 : {u: [v...]}
# return : 強連結成分のリスト (トポロジカルソート順)
def scc(n, adj) -> list:
    def dfs(node, used, acc):
        used[node] = True
        for to in adj[node]:
            if used[to]: continue
            dfs(to, used, acc)
        acc.append(node)

    def r_dfs(node, used, g):
        used[node] = True
        g.append(node)
        for to in radj[node]:
            if used[to]: continue
            r_dfs(to, used, g)

    radj = defaultdict(list)  # 逆辺
    for k, vs in adj.items():
        for v in vs:
            radj[v].append(k)

    acc = []
    used = [False] * n
    for i in range(n):
        if used[i]: continue
        dfs(i, used, acc)

    cc = []
    used = [False] * n
    for node in reversed(acc):
        if used[node]: continue
        g = []
        r_dfs(node, used, g)
        cc.append(g)
    return cc


N = int(input())
adj = defaultdict(list)
for i in range(N):
    M, *A = list(map(int, input().split()))
    for a in A:
        adj[i].append(a-1)


s = scc(N, adj)
tab = [-1] * N
g = defaultdict(list)
for i, cc in enumerate(s):
    for x in cc:
        tab[x] = i
        g[i].append(x)


def dfs(v):
    used.add(v)
    # 頂点 v の scc
    s = set()
    for cc in g[tab[v]]:
        #print(f'{v=} {cc=}')
        for to in adj[cc]:
            # 頂点 v とは異なる scc に属する
            used.add(to)
            if tab[v] != tab[to]:
                s.add(to)

    #print(f'{v=} {s=}')
    if len(s) > 1:
        print('No')
        exit()

    if len(s) == 1:
        dfs(list(s)[0])


used = set()
dfs(0)
#print(f'{len(used)=}')
if len(used) == N:
    print('Yes')
else:
    print('No')