def can_spread_to_all(N, connections):
    from collections import deque
    
    # グラフの隣接リストを構築
    graph = [[] for _ in range(N + 1)]
    for i, conn in enumerate(connections, 1):
        for person in conn:
            graph[i].append(person)
    
    # BFSで到達可能なノードを探索
    visited = [False] * (N + 1)
    queue = deque([1])
    visited[1] = True
    
    while queue:
        current = queue.popleft()
        for neighbor in graph[current]:
            if not visited[neighbor]:
                visited[neighbor] = True
                queue.append(neighbor)
    
    # 全てのノードに訪問できたかチェック
    return all(visited[1:])

# 入力を読み込む
import sys
input = sys.stdin.read
data = input().split()

N = int(data[0])
index = 1
connections = []

for _ in range(N):
    M = int(data[index])
    if M == 0:
        connections.append([])
    else:
        connections.append([int(data[i]) for i in range(index + 1, index + M + 1)])
    index += M + 1

if can_spread_to_all(N, connections):
    print("Yes")
else:
    print("No")