leaf = set()

def dfs(cv, pv, G, depth):
    is_leaf = True
    for nv in G[cv]:
        if nv == pv:
            continue
        dfs(nv, cv, G, depth + 1)
        is_leaf = False

    if is_leaf:
        leaf.add(depth)

n = int(input())
G = [[] for i in range(n)]
deg = [0 for i in range(n)]
for i in range(n - 1):
    a, b = map(int, input().split())
    a -= 1
    b -= 1
    deg[a] += 1
    deg[b] += 1
    G[a].append(b)
    G[b].append(a)

root = []
for i in range(n):
    if deg[i] == 1 and len(root) <= 10:
        root.append(i)

for i in root:
    dfs(i, -1, G, 0)

if len(leaf) == 1:
    print("Yes")
else:
    print("No")