{"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":"有n种口味的小吃,用整数1,2,…,n编号,每种口味各有一个。每个客人都有两种最喜欢的口味。吃零食的步骤如下:\n首先,用某种方式让客人排队。\n然后按照这个顺序,客人们会一个接一个地走向小吃。\n每位客人将他最喜欢的口味的小吃全部吃掉。如果客人上餐厅时没有任何他喜欢的口味,他们会很伤心。\n为了减少悲伤的客人的数量,请你以最佳的方式排列客人。"}},{"title":"Input","value":{"format":"HTML","content":"第一行包含整数n和k(2≤n≤1e5,1≤k≤1e5),零食数量和客人人数。\n下k行第i个包含第i位客人喜爱的零食口味的两个整数xi和yi(1≤xi,yi≤n, xi≠yi)。"}},{"title":"Output","value":{"format":"HTML","content":"输出一个整数,即合理排列后悲伤客户的最小可能数量。"}},{"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 Input\n \u003c/div\u003e\n \u003cpre\u003e5 4\n1 2\n4 3\n1 4\n3 4\n\u003c/pre\u003e\n \u003c/div\u003e\n \u003cdiv class\u003d\"output\"\u003e\n \u003cdiv class\u003d\"title\"\u003e\n Output\n \u003c/div\u003e\n \u003cpre\u003e1\n\u003c/pre\u003e\n \u003c/div\u003e\n \u003cdiv class\u003d\"input\"\u003e\n \u003cdiv class\u003d\"title\"\u003e\n Input\n \u003c/div\u003e\n \u003cpre\u003e6 5\n2 3\n2 1\n3 4\n6 5\n4 5\n\u003c/pre\u003e\n \u003c/div\u003e\n \u003cdiv class\u003d\"output\"\u003e\n \u003cdiv class\u003d\"title\"\u003e\n Output\n \u003c/div\u003e\n \u003cpre\u003e0\n\u003c/pre\u003e\n \u003c/div\u003e\n\u003c/div\u003e"}},{"title":"Sponser","value":{"format":"HTML","content":"\u003cpre\u003e\n样例1解释\n有5种小吃,4个客人\n第一个客人吃掉小吃1和2\n第三个客人吃掉小吃4\n第二个客人吃掉小吃3\n第四个客人没有喜欢的口味,很伤心。\n\u003c/pre\u003e"}}]}