{"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":"MD","content":" Mu Mu has n disciples, and he decided to choose some (maybe not) to form a group to train cooperation skills. Some of them are friends.\n For each pair of friends (x, y), if both of them are selected, the training result will increase by 1. If only one of them is selected, the training result will decrease by 1. If k students are selected, the training of the group The result will be reduced by k.\n Please output the maximum training result of the group."}},{"title":"Input","value":{"format":"MD","content":" The first line of the input gives the number of test cases, T (1≤T≤1e4). T test cases follow.\n\n For each test case, the first line contains two integers n (1≤n≤3e5) and m (1≤m≤1e6), where n is the number of students and m is the number of couples of friends.\n\n Each of the following m lines contains two integers xi,yi (1≤xi,yi≤n,xi≠yi), representing student xi and student yi are friends. It guaranteed that unordered pairs (xi,yi) are distinct.\n\n The sum of n in all test cases doesn\u0027t exceed 1e6, and the sum of m in all test cases doesn\u0027t exceed 2e6."}},{"title":"Output","value":{"format":"MD","content":" For each test case, output one line containing \"Case #x: y\", where x is the test case number (starting from 1), and y is the maximum friendly value of the group."}},{"title":"Example","value":{"format":"MD","content":"### Sample input\n 2\n 4 5\n 1 2\n 1 3\n 1 4\n 2 3\n 3 4\n 2 1\n 1 2\n### Sample output\n Case #1: 1\n Case #2: 0"}}]}