http:\/\/acm.hust.edu.cn\/vjudge\/problem\/viewSource.action?id=2815893<\/a><\/p>\nSee also http:\/\/www.codechef.com\/viewsolution\/4993836<\/p>\n
\r\n\r\n\/\/}\/* .................................................................................................................................. *\/\r\n\r\nconst int N = int(1e5) + 9, LV = 31;\r\nint n;\r\n\r\nvoid _r(int &x){\r\n x=reverse_bits(x); x>>=1;\r\n}\r\n\r\nnamespace T{\r\n\r\n int trans[N*LV][2];\r\n int nn;\r\n\r\n int new_node(){\r\n RST(trans[nn]);\r\n return nn++;\r\n }\r\n\r\n #define v trans[u][c]\r\n\r\n void Insert(int x){\r\n _r(x); int u = 0; REP(i, LV){\r\n int c = x & 1; x >>= 1;\r\n if (!v) v = new_node();\r\n u = v;\r\n }\r\n }\r\n int Query(int x){\r\n int z = 0, u = 0; _r(x); REP(i, LV){\r\n int c = (x & 1) ^ 1; x >>= 1; z <<= 1;\r\n if (!v) c ^= 1; else z |= 1;\r\n u = v;\r\n }\r\n return z;\r\n }\r\n void Init(){\r\n nn = 0; new_node();\r\n }\r\n};\r\n\r\n#define aa to[i^1]\r\n#define bb to[i]\r\n#define v bb\r\n#define w ww[i\/2]\r\n\r\nconst int M = N*2;\r\nint hd[N], suc[M], to[M], ww[N];\r\nint Xor[N], maxXor;\r\n\r\nvoid dfs(int u = 0, int p = -1){\r\n\r\n T::Insert(Xor[u]);\r\n checkMax(maxXor, T::Query(Xor[u]));\r\n\r\n REP_G(i, u) if (v != p){\r\n Xor[v] = Xor[u] ^ w;\r\n dfs(v, u);\r\n }\r\n}\r\n\r\n\r\nint main(){\r\n\r\n#ifndef ONLINE_JUDGE\r\n freopen("in.txt", "r", stdin);\r\n \/\/freopen("out.txt", "w", stdout);\r\n#endif\r\n\r\n while (~scanf("%d", &n)){\r\n\r\n fill(hd, hd+n, 0); FOR_C(i, 2, n<<1){\r\n RD(aa, bb, w);\r\n suc[i] = hd[aa], hd[aa] = i++;\r\n suc[i] = hd[aa], hd[aa] = i;\r\n }\r\n\r\n maxXor = 0; T::Init(); dfs();\r\n OT(maxXor);\r\n }\r\n}\r\n\r\n<\/pre>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","enabled":false}}},"categories":[1],"tags":[],"class_list":["post-1011","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/p2tdP7-gj","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/posts\/1011","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/comments?post=1011"}],"version-history":[{"count":1,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/posts\/1011\/revisions"}],"predecessor-version":[{"id":1013,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/posts\/1011\/revisions\/1013"}],"wp:attachment":[{"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/media?parent=1011"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/categories?post=1011"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/tags?post=1011"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}