import sys
sys.setrecursionlimit(10**7)
from functools import lru_cache

n = int(input())
li = [0]*n
ab = [[] for i in range(n)]
exit()
for i in range(n-1):
    a,b = map(int,input().split())
    a -= 1
    b -= 1
    ab[a].append(b)
    li[b] = 1

for i in range(n):
    if li[i] == 0:
        idx = i
        break

num = [0]*n

def dfs(v):
    if num[v] != 0:
        return num[v]
    for i in range(len(ab[v])):
        num[v] += dfs(ab[v][i])
    num[v] += 1
    return num[v]

dfs(idx)
exit()
dp = [-1]*n

@lru_cache(maxsize=n+1)
def dfs2(v):
    if dp[v] != -1:
        return dp[v]
    for i in range(len(ab[v])):
        dp[v] += dfs2(ab[v][i])+num[ab[v][i]]
    dp[v] += 1
    return dp[v]

dfs2(idx)
print(sum(dp))