import sys input = sys.stdin.readline sys.setrecursionlimit(10 ** 6) if "pypyjit" in sys.builtin_module_names: import pypyjit pypyjit.set_param("max_unroll_recursion=-1") N=int(input()) edge = [[] for _ in range(N)] XY=[list(map(int,input().split())) for _ in range(N-1)] for x,y in XY: x,y=x-1,y-1 edge[x].append(y) edge[y].append(x) visit = [0]*N from heapq import * def dfs(v=0): visit[v]=1 n_tree = [] for to in edge[v]: if visit[to]:continue n,lst = dfs(to) heappush(n_tree,-n) while lst: heappush(n_tree,heappop(lst)) ret = 1 for i in range(min(2,len(n_tree))): ret += -heappop(n_tree) return ret,n_tree ans,_ = dfs() print(ans)