import sys
#input = sys.stdin.readline
input = sys.stdin.buffer.readline #文字列はダメ
#sys.setrecursionlimit(1000000)
#import bisect
#import itertools
#import random
from heapq import heapify, heappop, heappush
#from collections import defaultdict 
#from collections import deque
#import copy
#import math
#from functools import lru_cache
#@lru_cache(maxsize=None)
#MOD = pow(10,9) + 7
#MOD = 998244353
#dx = [1,0,-1,0]
#dy = [0,1,0,-1]
#dx8 = [1,1,0,-1,-1,-1,0,1]
#dy8 = [0,1,1,1,0,-1,-1,-1]


def main():
    N = int(input())
    G = [[] for _ in range(N)]
    for i in range(N-1):
        x,y = map(int,input().split())
        x -= 1; y -= 1
        G[x].append(y)
        G[y].append(x)
    
    ans = 0
    par = [-1]*N
    children = [[] for _ in range(N)]
    stack = []
    stack.append(~0)
    stack.append(0)
    while stack:
        v = stack.pop()
        if v >= 0:
            for u in G[v]:
                if par[v] == u: continue
                par[u] = v
                stack.append(~u)
                stack.append(u)
        else:
            v = ~v
            VPQ = children[v]
            #子を全てチェックする。
            for u in G[v]:
                if par[v] == u: continue
                if len(children[u]) > len(VPQ):
                    VPQ, children[u] = children[u], VPQ
                    while children[u]:
                        num = heappop(children[u])
                        heappush(VPQ,-num)
            #print("v",v,VPQ)
            #大きいほうから最大2個と自分を親につける。
            temp = 1
            for _ in range(2):
                if VPQ:
                    score = -1 * heappop(VPQ)
                    temp += score
            #print("v",v,"temp",temp)
            #根であれば終了
            if v == 0:
                print(temp);exit()
            #残ったものと、採用するものをすべて親につける必要があるのでその前VPQにまとめる
            heappush(VPQ,-temp)
            if children[par[v]] < VPQ:
                children[par[v]], VPQ = VPQ, children[par[v]]
            while VPQ:
                num = heappop(VPQ)
                heappush(children[par[v]], num)
            

                
if __name__ == '__main__':
    main()