I told the Founders Forum two weeks ago that the last computer program I wrote was a Sudoku solver, written in C++ several years ago (http://bit.ly/1DMK5Zk). Someone asked me for it. Here is the source code, the exe file, and a sample printout - http://bit.ly/1zAXbua
The program is pretty basic: it runs at the command prompt, in a DOS window. Type in the data line by line (e.g. 1-3-8---6), then the solver will print out the solution (or all the solutions if there are several), the number of steps the program took searching for the solution, plus some search statistics.
For techies: the program does a backtrack search, choosing the next cell to guess which minimises the fanout.
Here’s a question for those reading the source code: if x is an (binary) integer, what does (x & -x) compute?
Hope you have fun playing with this. Please tell me if you find any bugs! – LHL
#SmartNation
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Answer: As several of you noted, (x & –x) returns the least significant ‘1’ bit of x, i.e. the highest power of two that divides x. This assumes two’s complement notation for negative numbers, as some of you also pointed out. e.g. if x=12 (binary 1100), then (x & -x) = 4 (binary 100). I didn’t invent this; it is an old programming trick. :)
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Update: A few people suggested that I add a licence to the code. Have added it in the Google Drive folder.
command a 在 [心得] 推台中command A維修- 看板iOS - 批踢踢實業坊 的八卦
手機聽筒從暑假壞現在一直都沒去修
之前有一次去一中的某家維修店換電池時
有提說聽筒壞掉想順便修
但店家直接就說要修的話八百塊也沒有要做測試的意思就直接修
後來因為換電池的過程覺得店家態度沒很好就算了
然後今天剛好在網路上有看到command A
就直接過去修了
一開始我也是跟對方說我聽筒聽不見
他們就先幫我測試然後換完聽筒發現還是沒聲音
跟我解釋可能是前置鏡面板壞掉或是防塵的什麼塞住了
後來發現是前置鏡的問題
過程中店員態度都很有耐心(我覺得有耐心超重要)
修完之後我的聽筒果真好了～
已經超久都只能用擴音講電話的我用聽筒聽到聲音那刻超感動
我是覺得這家服務滿好的啦而且我前置鏡原價900他們現在剛好有打9折
花點小錢讓我i5再戰一年也是值得～
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※ 編輯: mkchara002 (111.83.60.25), 02/22/2016 15:43:50
※ 編輯: mkchara002 (111.83.60.25), 02/22/2016 15:43:50
※ 編輯: mkchara002 (111.83.60.25), 02/22/2016 15:44:33
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