mod = 1000000007
eps = 10**-9


def main():
    import sys
    from collections import deque
    input = sys.stdin.buffer.readline

    N = int(input())
    adj = [[] for _ in range(N+1)]
    for _ in range(N-1):
        a, b = map(int, input().split())
        adj[a].append(b)
        adj[b].append(a)

    L = []
    for v in range(1, N+1):
        if len(adj[v]) > 2:
            L.append(v)
    if len(L) >= 2:
        print("No")
    elif len(L) == 0:
        print("Yes")
    else:
        v0 = L[0]
        que = deque()
        que.append(v0)
        seen = [-1] * (N+1)
        seen[v0] = 0
        par = [0] * (N+1)
        child = [[] for _ in range(N+1)]
        seq = []
        while que:
            v = que.popleft()
            seq.append(v)
            for u in adj[v]:
                if seen[u] == -1:
                    seen[u] = seen[v] + 1
                    par[u] = v
                    child[v].append(u)
                    que.append(u)
        seq.reverse()

        T = set()
        for v in range(1, N+1):
            if len(adj[v]) == 1:
                T.add(seen[v])
        if len(T) == 1:
            print("Yes")
        else:
            print("No")


if __name__ == '__main__':
    main()