from collections import deque

n = int(input())
rosen = [[] for _ in range(n+1)]
for i in range(n-1):
    a, b = map(int, input().split())
    rosen[a].append(b)
    rosen[b].append(a)
ans = set()

def bfs(start):
    queue = deque([start])
    d = [-1] * (n+1)
    d[start] = 0
    while queue:
        v = queue.popleft()
        for i in rosen[v]:
            if d[i] != -1:
                continue
            d[i] = d[v] + 1
            if d[i] <= 3:
                if start < i:
                    ans.add((start, i))
                else:
                    ans.add((i, start))
                queue.append(i)

for i in range(1, n+1):
    bfs(i)
print(len(ans))