{"code":"icpc21cointoss","name":"Coin Toss","description":"A sequence of coin toss can be encoded as a binary string, ’0’ for head, ’1’ for tail. Given an encoded sequence $S$,\r\ntoss the coin until $S$ appears in the result sequence then stop.\r\nLet $T$ be the number of coin toss taken for $S$ to appear, find the expected value of $T$.\r\n\r\n<h4>Input</h4>\r\n\r\nLet $T$ be the number of coin toss taken for $S$ to appear, find the expected value of $T$.\r\n\r\n<h4>Output</h4>\r\n\r\nLet $T$ be the number of coin toss taken for $S$ to appear, find the expected value of $T$.\r\n\r\n<h4>Example</h4>\r\n\r\n!!! question \"Test 1\"\r\n\r\n    ???+ \"Input\"\r\n        ```sample\r\n        1\r\n        00\r\n        ```\r\n    \r\n    ???+ success \"Output\"\r\n        ```sample\r\n        6\r\n        ```","points":400.0,"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}}