import sys
from collections import deque

input = sys.stdin.buffer.readline

n = int(input())
graph = [[] for _ in range(n)]
deg1 = [0] * n
deg2 = [0] * n
for _ in range(n - 1):
    a, b = map(int, input().split())
    a, b = a - 1, b - 1
    graph[a].append(b)
    graph[b].append(a)
    deg1[a] += 1
    deg1[b] += 1
root = -1
kouho = deque()
dist = [-1] * n
done = [0] * n
for i in range(n):
    if deg1[i] != 1:
        root = i
    if deg1[i] == 1:
        kouho.append(i)
        dist[i] = 0
        done[i] = 1


def ok():
    print("Yes")
    exit()


def ng():
    print("No")
    exit()


if root == -1:
    if n == 2:
        ok()
    else:
        ng()


# bfs
# print("kouho", kouho)

while kouho:
    v = kouho.popleft()
    d = dist[v]
    for u in graph[v]:
        done[u] = 1
        if dist[u] == -1:
            dist[u] = d + 1
            kouho.append(u)
        else:
            if dist[u] != d + 1 and dist[u] != d - 1:
                # print("ng", v, u)
                ng()

ok()