from collections import deque


N = int(input())

G = [[] for _ in range(N)]
for _ in range(N - 1):
	u, v = map(int, input().split())
	u -= 1; v -= 1;
	G[u].append(v)
	G[v].append(u)

ans = 0
for i in range(N):
	bfs = deque()
	bfs.append(i)
	d = [-1] * N
	d[i] = 0
	while bfs:
		u = bfs.popleft()
		for v in G[u]:
			if d[u] < 3 and d[v] == -1:
				bfs.append(v)
				d[v] = d[u] + 1
				ans += 1

print(ans // 2)