{"code":"cppb1p302","name":"Tổng chẵn","description":"In ra tổng các số chẵn từ 1 đến $n$.\r\n\r\n#### Input\r\n - Ghi số $n$; $(0 \\le n \\leq 10^5)$.\r\n\r\n#### Output\r\n - In ra bài toán.\r\n\r\n#### Example\r\n\r\n???+ question \"Test 1\"\r\n    ???+ \"Input\"\r\n        ```sample\r\n        5\r\n        ```\r\n    \r\n    ???+ success \"Output\"\r\n        ```sample\r\n        6\r\n        ```\r\n\r\n???+ question \"Test 2\"\r\n    ???+ \"Input\"\r\n        ```sample\r\n        10\r\n        ```\r\n    \r\n    ???+ success \"Output\"\r\n        ```sample\r\n        30\r\n        ```","points":100.0,"partial":false,"time_limit":1.0,"memory_limit":262144,"short_circuit":false,"allowed_languages":[3,4,34,36,37,5,6,11,12,14,28,2,38,39,9,18,17,29,23,27,35,25,26,10,7,19,32,1,8,15,16,24,20,33,13,41,21,40],"is_public":true,"is_manually_managed":false,"permissions":{"can_edit":false}}