###UnionFind### from collections import defaultdict class UnionFind(): """ Union Find木クラス Attributes -------------------- n : int 要素数 root : list 木の要素数 0未満であればそのノードが根であり、添字の値が要素数 rank : list 木の深さ """ def __init__(self, n): """ Parameters --------------------- n : int 要素数 """ self.n = n self.root = [-1]*(n+1) self.rank = [0]*(n+1) def find(self, x): """ ノードxの根を見つける Parameters --------------------- x : int 見つけるノード Returns --------------------- root : int 根のノード """ if(self.root[x] < 0): return x else: self.root[x] = self.find(self.root[x]) return self.root[x] def unite(self, x, y): """ 木の併合 Parameters --------------------- x : int 併合したノード y : int 併合したノード """ x = self.find(x) y = self.find(y) if(x == y): return elif(self.rank[x] > self.rank[y]): self.root[x] += self.root[y] self.root[y] = x else: self.root[y] += self.root[x] self.root[x] = y if(self.rank[x] == self.rank[y]): self.rank[y] += 1 def same(self, x, y): """ 同じグループに属するか判定 Parameters --------------------- x : int 判定したノード y : int 判定したノード Returns --------------------- ans : bool 同じグループに属しているか """ return self.find(x) == self.find(y) def size(self, x): """ 木のサイズを計算 Parameters --------------------- x : int 計算したい木のノード Returns --------------------- size : int 木のサイズ """ return -self.root[self.find(x)] def roots(self): """ 根のノードを取得 Returns --------------------- roots : list 根のノード """ return [i for i, x in enumerate(self.root) if x < 0] def group_size(self): """ グループ数を取得 Returns --------------------- size : int グループ数 """ return len(self.roots()) - 1 def group_members(self): """ 全てのグループごとのノードを取得 Returns --------------------- group_members : defaultdict 根をキーとしたノードのリスト """ group_members = defaultdict(list) for member in range(self.n): group_members[self.find(member)].append(member) return group_members ###素因数分解### def prime_factorize(n: int) -> list: return_list = [] while n % 2 == 0: return_list.append(2) n //= 2 f = 3 while f * f <= n: if n % f == 0: return_list.append(f) n //= f else: f += 2 if n != 1: return_list.append(n) return return_list ###ある数が素数かどうかの判定### import math def is_prime(n): sqrt_n = math.ceil(math.sqrt(n)) for i in range(2, sqrt_n): if n % i == 0: return False return True ###N以下の素数列挙### import math def sieve_of_eratosthenes(n): prime = [True for i in range(n+1)] prime[0] = False prime[1] = False sqrt_n = math.ceil(math.sqrt(n)) for i in range(2, sqrt_n+1): if prime[i]: for j in range(2*i, n+1, i): prime[j] = False return prime ###N以上K以下の素数列挙### import math def segment_sieve(a, b): sqrt_b = math.ceil(math.sqrt(b)) prime_small = [True for i in range(sqrt_b)] prime = [True for i in range(b-a+1)] for i in range(2, sqrt_b): if prime_small[i]: for j in range(2*i, sqrt_b, i): prime_small[j] = False for j in range((a+i-1)//i*i, b+1, i): #print('j: ', j) prime[j-a] = False return prime ###n進数から10進数変換### def base_10(num_n,n): num_10 = 0 for s in str(num_n): num_10 *= n num_10 += int(s) return num_10 ###10進数からn進数変換### def base_n(num_10,n): str_n = '' while num_10: if num_10%n>=10: return -1 str_n += str(num_10%n) num_10 //= n return int(str_n[::-1]) ###複数の数の最大公約数、最小公倍数### from functools import reduce # 最大公約数 def gcd_list(num_list: list) -> int: return reduce(gcd, num_list) # 最小公倍数 def lcm_base(x: int, y: int) -> int: return (x * y) // gcd(x, y) def lcm_list(num_list: list): return reduce(lcm_base, num_list, 1) ###約数列挙### def make_divisors(n): lower_divisors, upper_divisors = [], [] i = 1 while i * i <= n: if n % i == 0: lower_divisors.append(i) if i != n // i: upper_divisors.append(n//i) i += 1 return lower_divisors + upper_divisors[::-1] ###順列### def nPr(n, r): npr = 1 for i in range(n, n-r, -1): npr *= i return npr ###組合せ### def nCr(n, r): factr = 1 r = min(r, n - r) for i in range(r, 1, -1): factr *= i return nPr(n, r)/factr import sys, re from fractions import Fraction from math import ceil, floor, sqrt, pi, factorial, gcd from copy import deepcopy from collections import Counter, deque, defaultdict from heapq import heapify, heappop, heappush from itertools import accumulate, product, combinations, combinations_with_replacement, permutations from bisect import bisect, bisect_left, bisect_right from functools import reduce from decimal import Decimal, getcontext def i_input(): return int(input()) def i_map(): return map(int, input().split()) def i_list(): return list(i_map()) def i_row(N): return [i_input() for _ in range(N)] def i_row_list(N): return [i_list() for _ in range(N)] def s_input(): return input() def s_map(): return input().split() def s_list(): return list(s_map()) def s_row(N): return [s_input for _ in range(N)] def s_row_str(N): return [s_list() for _ in range(N)] def s_row_list(N): return [list(s_input()) for _ in range(N)] def lcm(a, b): return a * b // gcd(a, b) def get_distance(x1, y1, x2, y2): d = sqrt((x2 - x1) ** 2 + (y2 - y1) ** 2) return d def rotate(table): n_fild = [] for x in zip(*table[::-1]): n_fild.append(x) return n_fild sys.setrecursionlimit(10 ** 7) INF = float('inf') MOD = 10 ** 9 + 7 MOD2 = 998244353 ###関数コピーしたか？### def main(): n = int(input()) lines = [] for i in range(int(n*(n-1)/2)): a, b, c = i_map() lines.append([c, a, b]) lines.sort(key=lambda x:(x[0], x[1])) uf = UnionFind(n) now = lines[0][0] for i in range(int(n*(n-1)/2)): score, x, y = lines[i] if uf.same(x, y): print(now) exit() else: uf.unite(x, y) now = score print(now) if __name__ == '__main__': main()