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O(nlogn) Algorithm - Find three evenly spaced ones within binary string

....3^n-1 not containing 1 in their ternary expansion) - its density is n^(log_3 2) (circa 0.631). So any checking if the set isn't too large, and then checking all pairs is not enough to get O(n log n). You have to investigate the sequence smarter. A better lower bound is quoted here - it's n1-c/(log(...
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Extracting numbers from vectors of strings

...meric(gsub("([0-9]+).*$", "\\1", years)) or # pattern is to just remove _years_old as.numeric(gsub(" years old", "", years)) or # split by space, get the element in first index as.numeric(sapply(strsplit(years, " "), "[[", 1)) ...
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What's the difference between Task.Start/Wait and Async/Await?

...ll update the label! UpdateLabelToSayItsComplete(); } public void Button_2_Click(object sender, EventArgs e) { Console.WriteLine("Button 2 Clicked"); } private void DoSomethingThatTakesTime() { Thread.Sleep(10000); } ...
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find() with nil when there are no records

... Yes, just do: Challenge.find_by_id(10) For Rails 4 and 5: Challenge.find_by(id: 10) share | improve this answer | follow ...
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How does having a dynamic variable affect performance?

...Generator(); if (!method.IsStatic) { il.Emit(OpCodes.Ldarg_0); il.Emit(OpCodes.Unbox_Any, method.DeclaringType); } var parameters = method.GetParameters(); for (int i = 0; i < parameters.Length; i++) { il.Emit(OpCodes.Ldarg_1); il.Emit(OpCo...
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fatal error: malformed or corrupted AST file - Xcode

... Thanks man, this worked. But can you please explain what is all this about_ I like to know why something happens, when it does. And I just had this error when I opened my project the next day, out of the blue. – SteBra Jul 23 '14 at 8:27 ...
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How do I generate random numbers in Dart?

...0.9 ... the result would be for example -0.32 – just_a_dude Nov 7 '13 at 13:59 2 ...
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DateTime.ToString() format that can be used in a filename or extension?

...our file name. Here i have provided example string fileName = "fileName_" + DateTime.Now.ToString("MM-dd-yyyy_hh-mm-ss-tt") + ".pdf"; OR If you don't prefer to use symbols you can try this also., string fileName = "fileName_" + DateTime.Now.ToString("MMddyyyyhhmmsstt") + ".pdf"; Hope this ...
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What is the difference between a definition and a declaration?

...declares foo } ... or is a typedef or using statement. typedef long LONG_32; // declares LONG_32 using namespace std; // declares std Now for the big reason why it's important to understand the difference between a declaration and definition: the One Definition Rule. From section 3.2.1 of t...
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How do you check whether a number is divisible by another number (Python)?

... @Chris_Rands Put that into an answer, people who do code-golf (like me) would be very happy. In fact, I came here looking for a golfed answer like that. – MilkyWay90 Nov 11 '18 at 22:29 ...