{"trustable":false,"prependHtml":"\u003cstyle type\u003d\u0027text/css\u0027\u003e\n .input, .output {\n border: 1px solid #888888;\n }\n .output {\n margin-bottom: 1em;\n position: relative;\n top: -1px;\n }\n .output pre, .input pre {\n background-color: #EFEFEF;\n line-height: 1.25em;\n margin: 0;\n padding: 0.25em;\n }\n \u003c/style\u003e\n \u003clink rel\u003d\"stylesheet\" href\u003d\"//codeforces.org/s/96598/css/problem-statement.css\" type\u003d\"text/css\" /\u003e\u003cscript\u003e window.katexOptions \u003d { disable: true }; \u003c/script\u003e\n\u003cscript type\u003d\"text/x-mathjax-config\"\u003e\n MathJax.Hub.Config({\n tex2jax: {\n inlineMath: [[\u0027$$$\u0027,\u0027$$$\u0027], [\u0027$\u0027,\u0027$\u0027]],\n displayMath: [[\u0027$$$$$$\u0027,\u0027$$$$$$\u0027], [\u0027$$\u0027,\u0027$$\u0027]]\n }\n });\n\u003c/script\u003e\n\u003cscript type\u003d\"text/javascript\" async src\u003d\"https://mathjax.codeforces.org/MathJax.js?config\u003dTeX-AMS_HTML-full\"\u003e\u003c/script\u003e","sections":[{"title":"description","value":{"format":"MD","content":"给定一颗$n$个点的树,结点$i$上有一个字符$c_i$,$m$次询问对于给定的$a$,$b$,$c$,$d$,求$LCP(s(a,b),s(c,d))$。\n其中$s(i,j)$表示树上从$i$到$j$的简单路径所组成的字符串,$LCP$表示最长公共前缀。\n"}},{"title":"Input","value":{"format":"MD","content":"第一行一个整数$n$。\n接下来$n - 1$行表示这棵树。\n接下来一个整数$m$。\n接下来$m$行每行四个整数$a,b,c,d$表示一组询问。"}},{"title":"Output","value":{"format":"MD","content":"输出$m$行表示每组询问的答案。"}},{"title":"Sample 1","value":{"format":"MD","content":"\u003ctable class\u003d\u0027vjudge_sample\u0027\u003e\n\u003cthead\u003e\n \u003ctr\u003e\n \u003cth\u003eInput\u003c/th\u003e\n \u003cth\u003eOutput\u003c/th\u003e\n \u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\u003cpre\u003e6\nbbbabb\n2 1\n3 2\n4 3\n5 2\n6 5\n6\n2 5 3 1\n1 5 2 3\n5 6 5 6\n6 3 4 1\n6 2 3 4\n2 2 4 5\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003e2\n2\n2\n0\n1\n0\n\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}},{"title":"data domain","value":{"format":"MD","content":"$1 \\le n \\le 3 \\cdot 10^5$,$1 \\le m \\le 10^6$"}}]}