看板 puzzle 關於我們 聯絡資訊
題目網址: http://www.puzzleup.com/2016/ http://www.puzzleup.com/2016/puzzle/?17 答題時限: 11月17日7PM-比賽結束(約12月14日) 加分時限: 11月17日7PM-11月23日6:59PM 答對可得基本分100分。答案可上傳5次,每改1次答案從基本分扣20分。  比賽期間內可隨時上傳答案,加分時限內答對第n天加(6-n)分        另依題目的難易有額外加分(如有80%的人這題答錯,答對者加80分)   ◆SEVEN There is a number with digits appearing at most twice and all the numbers formed by adjacent two digits are divisible by 7. What can be the maximum value for this number? Example:63563 is such a number (63, 35, 56 and 63 are divisible by 7) but it is not the maximum. 有此一數,其每個數字至多出現兩次,且所有相鄰兩位數所形成的數皆可被 7 整除。 問此數最大為何? 例: 63563 為符合條件的一數 (63、35、56、63 皆可被 7 整除),但並非最大。 -- 'You've sort of made up for it tonight,' said Harry. 'Getting the sword. Finishing the Horcrux. Saving my life.' 'That makes me sound a lot cooler then I was,' Ron mumbled. 'Stuff like that always sounds cooler then it really was,' said Harry. 'I've been trying to tell you that for years.' -- Harry Potter and the Deathly Hollows, P.308 -- ※ 發信站: 批踢踢實業坊(ptt.cc), 來自: 140.112.30.32 ※ 文章網址: https://www.ptt.cc/bbs/puzzle/M.1479329370.A.C06.html
ddtddt: 有趣 11/17 08:57
buffalobill: 這題也太簡單了吧... 11/17 10:14
prime2477: Longest path problem 的變形? 11/17 23:53