{"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":"","value":{"format":"HTML","content":"\u003cp\u003e对于一个字符串,关键子串定义为:这个字符串的一个子串,既是这个字符串的前缀,也是这个字符串的后缀,同时在除了前缀及后缀的位置作为子串出现过。\u003c/p\u003e\n\u003cp\u003e现在给出一个字符串 \u003cb\u003es\u003c/b\u003e,输出它的最长关键子串 \u003cb\u003et\u003c/b\u003e。\u003c/p\u003e"}},{"title":"Input","value":{"format":"HTML","content":"\u003cp\u003e输入只有一个字符串 \u003cb\u003es\u003c/b\u003e,长度在 \u003cb\u003e1\u003c/b\u003e 到 \u003cb\u003e10\u003csup\u003e6\u003c/sup\u003e\u003c/b\u003e 之间,只包含小写字母。\u003c/p\u003e"}},{"title":"Output","value":{"format":"HTML","content":"\u003cp\u003e输出一个字符串,表示最长的关键子串。无解则输出 \u003cb\u003e\"Just a legend\"\u003c/b\u003e(不含双引号)。\u003c/p\u003e"}},{"title":"Examples","value":{"format":"HTML","content":"\u003cdiv class\u003d\"sample-test\"\u003e \n \u003cdiv class\u003d\"input\"\u003e \n \u003cdiv class\u003d\"title\"\u003e\n 输入\n \u003c/div\u003e \n \u003cpre\u003efixprefixsuffix\u003cbr\u003e\u003c/pre\u003e\n \u003c/div\u003e \n \u003cdiv class\u003d\"output\"\u003e \n \u003cdiv class\u003d\"title\"\u003e\n 输出\n \u003c/div\u003e \n \u003cpre\u003efix\u003c/pre\u003e\n \u003c/div\u003e \n \u003cdiv class\u003d\"input\"\u003e \n \u003cdiv class\u003d\"title\"\u003e\n 输入\n \u003c/div\u003e \n \u003cpre\u003eabcdabc\u003cbr\u003e\u003c/pre\u003e\n \u003c/div\u003e \n \u003cdiv class\u003d\"output\"\u003e \n \u003cdiv class\u003d\"title\"\u003e\n 输出\n \u003c/div\u003e \n \u003cpre\u003eJust a legend\u003c/pre\u003e\n \u003c/div\u003e\n\u003c/div\u003e"}}]}