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What is a Context Free Grammar?
...to me what a context free grammar is? After looking at the Wikipedia entry and then the Wikipedia entry on formal grammar, I am left utterly and totally befuddled. Would someone be so kind as to explain what these things are?
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Xcode: What is a target and scheme in plain language?
... it :-) What do they mean in plain English language? I really don't understand the explanation on Apple's website and I need to rename my target and I'm afraid that nothing works after that..
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How do you create a random string that's suitable for a session ID in PostgreSQL?
I'd like to make a random string for use in session verification using PostgreSQL. I know I can get a random number with SELECT random() , so I tried SELECT md5(random()) , but that doesn't work. How can I do this?
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difference between socket programming and Http programming
What is the difference between socket programming and Http programming? can anyone help please?
5 Answers
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What is the difference between trie and radix trie data structures?
Are the trie and radix trie data structures the same thing?
3 Answers
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Releasing memory in Python
...llocator. The int type maintains a freelist with its own allocated memory, and clearing it requires calling PyInt_ClearFreeList(). This can be called indirectly by doing a full gc.collect.
Try it like this, and tell me what you get. Here's the link for psutil.Process.memory_info.
import os
import...
How important is the order of columns in indexes?
... Also keep in mind, suppose your Index is like the picture above, and your query filters on column1 and column2, but column2 is more unique and what you really want to filter on is actually column2, then its more beneficial to just have a index where column 2 is first. This may seem counte...
Should I use px or rem value units in my CSS? [closed]
I am designing a new website and I want it to be compatible with as much browsers and browser settings as possible. I am trying to decide what unit of measurement I should use for the sizes of my fonts and elements, but am unable to find a conclusive answer.
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Difference between Grunt, NPM and Bower ( package.json vs bower.json )
I'm new to using npm and bower, building my first app in emberjs :).
I do have a bit of experience with rails, so I'm familiar with the idea of files for listing dependencies (such as bundler Gemfile)
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Environment variables for java installation
...A_TOOL_OPTIONS with value -Dfile.encoding="UTF-8". This ensures that Java (and tools such as Maven) will run with a Charset.defaultCharset() of UTF-8 (instead of the default Windows-1252). This has saved a lot of headaches when wirking with my own code and that of others, which unfortunately often a...