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Python combine two lists of unequal length in alternating fashion

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问题 I have a two lists, and I want to combine them in an alternating fashion, until one runs out, and then I want to keep adding elements from the longer list. Aka. list1 = [a,b,c] list2 = [v,w,x,y,z] result = [a,v,b,w,c,x,y,z] Similar to this question (Pythonic way to combine two lists in an alternating fashion?), except in these the lists stop combining after the first list has run out :(. 回答1: Here is the simpler version from the excellent toolz: >>> interleave([[1,2,3,4,5,6,7,],[0,0,0]]) [1,

Python combine two lists of unequal length in alternating fashion

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Why does ListBox AlternationIndex always return 0

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问题 Ok, I know there are a couple of other similar questions to this but I am having a real issue with getting the AlternationIndex to work on ListBox or ListView. my xaml is such: <ListBox BorderThickness="0" Name="RecentItemsListBox" HorizontalAlignment="Stretch" ScrollViewer.HorizontalScrollBarVisibility="Disabled" ItemsSource="{Binding Path=RecentFilesList}" AlternationCount="100"> <ListBox.ItemsPanel> <ItemsPanelTemplate> <WrapPanel /> </ItemsPanelTemplate> </ListBox.ItemsPanel> <ListBox

Why regex engine choose to match pattern `..X` from `.X|..X|X.`?

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问题 I have a string 1234X5678 and I use this regex to match pattern .X|..X|X. I got 34X The question is why didn't I get 4X or X5 ? Why regex choose to perform the second pattern? 回答1: The main point here is: Regex engine analyzes the input from LEFT TO RIGHT by default. So, you have an alternation pattern .X|..X|X. and you run it against 1234X5678 . See what happens: Each alternative branch is tested against each location in the string from left to right . The first 1-7 steps show how the engine

Why won't a longer token in an alternation be matched?

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问题 I am using ruby 2.1, but the same thing can be replicated on rubular site. If this is my string: 儘管中國婦幼衛生監測辦公室制定的 And I do a regex match with this expression: (中國婦幼衛生監測辦公室制定|管中) I am expecting to get the longer token as a match. 中國婦幼衛生監測辦公室制定 Instead I get the second alternation as a match. As far as I know it does work like that when not in chinese characters. If this is my string: foobar And I use this regex: (foobar|foo) Returned matching result is foobar . If the order is in the other way

Regex is behaving lazy, should be greedy

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问题 I thought that by default my Regex would exhibit the greedy behavior that I want, but it is not in the following code: Regex keywords = new Regex(@"in|int|into|internal|interface"); var targets = keywords.ToString().Split('|'); foreach (string t in targets) { Match match = keywords.Match(t); Console.WriteLine("Matched {0,-9} with {1}", t, match.Value); } Output: Matched in with in Matched int with in Matched into with in Matched internal with in Matched interface with in Now I realize that I

How to make alternating turns in Java?

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问题 I'm in 9th grade in AP computer science and we were given a project to make a game. I picked a simple Game of Chi thing that my teacher had suggested. But what I cannot figure out is how to make alternating turns between the computer and the player. import java.util.Scanner; /** * Game of Chi .. see main for gameplay * * @author ..... */ public class GameOfChi { private static int numStonesLeft = 0; public static void main(String[] args) { numStonesLeft = (int) (Math.random() * 16) + 15;//

How to make alternating turns in Java?

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I'm in 9th grade in AP computer science and we were given a project to make a game. I picked a simple Game of Chi thing that my teacher had suggested. But what I cannot figure out is how to make alternating turns between the computer and the player. import java.util.Scanner; /** * Game of Chi .. see main for gameplay * * @author ..... */ public class GameOfChi { private static int numStonesLeft = 0; public static void main(String[] args) { numStonesLeft = (int) (Math.random() * 16) + 15;// btw 15 & 30 stones System.out.println("This is the Game of Chi."); System.out.println("There is a pile of

Why regex engine choose to match pattern `..X` from `.X|..X|X.`?

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I have a string 1234X5678 and I use this regex to match pattern .X|..X|X. I got 34X The question is why didn't I get 4X or X5 ? Why regex choose to perform the second pattern? The main point here is: Regex engine analyzes the input from LEFT TO RIGHT by default. So, you have an alternation pattern .X|..X|X. and you run it against 1234X5678 . See what happens : Each alternative branch is tested against each location in the string from left to right . The first 1-7 steps show how the engine tries to match the characters at the beginning of the string. However, none of the branches (neither .X ,

Is it faster to use alternation than subsequent replacements in regular expressions

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问题 I have quite a straightforward question. Where I work I see a lot of regular expressions come by. They are used in Perl to get replace and/or get rid of some strings in text, e.g.: $string=~s/^.+\///; $string=~s/\.shtml//; $string=~s/^ph//; I understand that you cannot concatenate the first and last replacement, because you may only want to replace ph at the beginning of the string after you did the first replacement. However, I would put the first and second regex together with alternation: