---{"category_name":"school","problem_code":"BLACKCEL","problem_name":"Black cells in a chessboard","problemComponents":{"constraints":"- $2 \\leq n \\leq 100$\n- $n$ is even","constraintsState":true,"subtasks":"","subtasksState":false,"inputFormat":"The only line of the input contains a single integer $n$.","inputFormatState":true,"outputFormat":"Output the number of black cells in an $n \\times n$ chessboard.","outputFormatState":true,"sampleTestCases":{"0":{"id":1,"input":8,"output":32,"explanation":"\u003Cimg src=\u0022https://s3.amazonaws.com/codechef_shared/download/Images/DAANISH/Chess_Board.svg\u0022 height=\u0022200\u0022 width=\u0022200\u0022/\u003E\n\nThere are $32$ black cells and $32$ white cells in an $8 \\times 8$ chessboard. So the answer is $32$.","isDeleted":false}}},"video_editorial_url":"https://youtu.be/HfvxPvhkURA","languages_supported":{"0":"CPP14","1":"C","2":"JAVA","3":"PYTH 3.6","4":"CPP17","5":"PYTH","6":"PYP3","7":"CS2","8":"ADA","9":"PYPY","10":"TEXT","11":"PAS fpc","12":"NODEJS","13":"RUBY","14":"PHP","15":"GO","16":"HASK","17":"TCL","18":"PERL","19":"SCALA","20":"LUA","21":"kotlin","22":"BASH","23":"JS","24":"LISP sbcl","25":"rust","26":"PAS gpc","27":"BF","28":"CLOJ","29":"R","30":"D","31":"CAML","32":"FORT","33":"ASM","34":"swift","35":"FS","36":"WSPC","37":"LISP clisp","38":"SQL","39":"SCM guile","40":"PERL6","41":"ERL","42":"CLPS","43":"ICK","44":"NICE","45":"PRLG","46":"ICON","47":"COB","48":"SCM chicken","49":"PIKE","50":"SCM qobi","51":"ST","52":"SQLQ","53":"NEM"},"max_timelimit":0.5,"source_sizelimit":50000,"problem_author":"utkarsh_adm","problem_tester":"","date_added":"13-08-2021","tags":{"0":"cakewalk","1":"start9","2":"utkarsh_adm"},"problem_difficulty_level":"Cakewalk","best_tag":"","editorial_url":"https://discuss.codechef.com/problems/BLACKCEL","time":{"view_start_date":1629221400,"submit_start_date":1629221400,"visible_start_date":1629221400,"end_date":1735669800},"is_direct_submittable":false,"problemDiscussURL":"https://discuss.codechef.com/search?q=BLACKCEL","is_proctored":false,"visitedContests":{},"layout":"problem"}---### Read problem statements in [Mandarin Chinese](https://www.codechef.com/download/translated/START9/mandarin/BLACKCEL.pdf) and [Bengali](https://www.codechef.com/download/translated/START9/bengali/BLACKCEL.pdf).Given $n$ ($n$ is **even**), determine the number of **black cells** in an $n \times n$ chessboard.<aside style='background: #f8f8f8;padding: 10px 15px;'><div>All submissions for this problem are available.</div></aside>