import sys
import io, os
input = io.BytesIO(os.read(0,os.fstat(0).st_size)).readline

n = int(input())
g = [[] for i in range(n)]
for i in range(n-1):
    a, b = map(int, input().split())
    a, b = a-1, b-1
    g[a].append(b)
    g[b].append(a)

G = []
L = []
for i in range(n):
    if len(g[i]) >= 3:
        G.append(i)
    if len(g[i]) == 1:
        L.append(i)

if len(G) >= 2:
    print('No')
    exit()

if not G:
    print('Yes')
    exit()

s = G[0]
from collections import deque
q = deque([])
q.append(s)
dist = [-1]*n
dist[s] = 0
while q:
    v = q.popleft()
    for u in g[v]:
        if dist[u] == -1:
            dist[u] = dist[v]+1
            q.append(u)
D = set()
for l in L:
    D.add(dist[l])
#print(D)
if len(D) == 1:
    print('Yes')
else:
    print('No')