from collections import defaultdict, deque
import sys
sys.setrecursionlimit(10**6)

N = int(input())

degs = [0] * N
adj = defaultdict(list)
for _ in range(N-1):
    U, V = map(lambda x: int(x)-1, input().split())
    adj[U].append(V)
    adj[V].append(U)

    degs[U] += 1
    degs[V] += 1

leaves = []
for i in range(N):
    if degs[i] == 1:
        leaves.append(i)


def f(w):
    used = set()

    def dfs(vs):
        hd = vs[0]
        tl = vs[-1]
        mi = min(hd, tl)
        ma = max(hd, tl)
        if mi != -1:
            used.add((mi, ma))

        for to in adj[tl]:
            if to == vs[-2]: continue

            xs = vs[1:] + [to]
            dfs(xs)

    for v in leaves:
        vs = [-1] * w
        vs[-1] = v
        dfs(vs)

    return len(used)


ans = f(2) + f(3) + f(4)
print(ans)