{"trustable":false,"prependHtml":"\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 async src\u003d\"https://mathjax.codeforces.org/MathJax.js?config\u003dTeX-AMS-MML_HTMLorMML\" type\u003d\"text/javascript\"\u003e\u003c/script\u003e","sections":[{"title":"","value":{"format":"HTML","content":"\u003cscript type\u003d\u0027text/x-mathjax-config\u0027\u003eMathJax.Hub.Config({tex2jax: { inlineMath: [[\u0027$\u0027,\u0027$\u0027]] } }); \u003c/script\u003e\n\u003cscript type\u003d\u0027text/javascript\u0027 src\u003d\u0027https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.1/MathJax.js?config\u003dTeX-AMS-MML_HTMLorMML\u0027\u003e\u003c/script\u003e\n\u003cscript type\u003d\u0027text/javascript\u0027\u003esetTimeout(function(){MathJax.Hub.Queue([\u0027Typeset\u0027, MathJax.Hub, \u0027left_view\u0027]);}, 2000);\u003c/script\u003e\n\u003cdiv class\u003d\"panel_content\"\u003e\n phz和他的手办喜欢在学校里散步,假设学校有N块空地,任意两块空地之间都有一条小径相通。他们每次从任意一块空地出发,经过所有的空地后回到原来的空地。\n \u003cbr\u003e由于他们都喜欢新鲜的旅行,所以他们不希望对任何一条小径经过两次。那么请问,他们最多能保证多少次这种新鲜的旅行呢? \n \u003cbr\u003e例如(图),当N\u003d5时,他们只能保持两次这样新鲜的旅行。 \n \u003cbr\u003e\n \u003ccenter\u003e\n \u003cimg style\u003d\"max-width:100%;\" src\u003d\"CDN_BASE_URL/496053710aca52adc198b4f6756e7daf?v\u003d1628964261\"\u003e\n \u003c/center\u003e\n\u003c/div\u003e"}},{"title":"Input","value":{"format":"HTML","content":"输入包含多组数据,每组数据占一行,是一个数字 N。(0\u0026lt;N\u0026lt;\u003d1000000000) \n\u003cbr\u003e文件以一个0结束。\n\u003cbr\u003e"}},{"title":"Output","value":{"format":"HTML","content":"对于每个输入的N,输出最多能保证新鲜旅行的次数。\n\u003cbr\u003e"}},{"title":"Sample Input","value":{"format":"HTML","content":"\u003cpre\u003e5\n0\u003c/pre\u003e"}},{"title":"Sample Output","value":{"format":"HTML","content":"\u003cpre\u003e2\u003c/pre\u003e"}}]}