import sys

sys.setrecursionlimit(10 ** 6)

def II(): return int(sys.stdin.readline())
def MI(): return map(int, sys.stdin.readline().split())
def LI(): return list(map(int, sys.stdin.readline().split()))
def SI(): return sys.stdin.readline()[:-1]
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
int1 = lambda x: int(x) - 1
def MI1(): return map(int1, sys.stdin.readline().split())
def LI1(): return list(map(int1, sys.stdin.readline().split()))
p2D = lambda x: print(*x, sep="\n")
dij = [(1, 0), (0, 1), (-1, 0), (0, -1)]

def dfs(root):
    stack=[(root,1)]
    while stack:
        u,d=stack.pop()
        if dp[u]==-1:
            dp[u]=0
            stack.append((u,d))
            for v in to[u]:
                stack.append((v,d+1))
        else:
            for v in to[u]:
                sz[u]+=sz[v]
                dp[u]+=dp[v]+d*sz[v]

n=II()
to=[[] for _ in range(n)]
isroot=[True]*n
for _ in range(n-1):
    u,v=MI1()
    to[u].append(v)
    isroot[v]=False
sz=[1]*n
dp=[-1]*n
for root in range(n):
    if isroot[root]:
        dfs(root)
        print(dp[root])
        break