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Single quotes vs. double quotes in C or C++
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In C and in C++ single quotes identify a single character, while double quotes create a string literal. 'a' is a single a character literal, while "a" is a string literal containing an 'a' and a null terminator (that is a 2 char array).
In C++ the type of a character lite...
NULL values inside NOT IN clause
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Query A is the same as:
select 'true' where 3 = 1 or 3 = 2 or 3 = 3 or 3 = null
Since 3 = 3 is true, you get a result.
Query B is the same as:
select 'true' where 3 <> 1 and 3 <> 2 and 3 <> null
When ansi_nulls is on, 3 <&...
How can I make Visual Studio wrap lines at 80 characters?
...ions >> Text Editor >> All Languages >> General >> Select Word Wrap.
I dont know if you can select a specific number of columns?
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Count the number occurrences of a character in a string
What's the simplest way to count the number of occurrences of a character in a string?
19 Answers
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How can I increment a char?
I'm new to Python, coming from Java and C. How can I increment a char? In Java or C, chars and ints are practically interchangeable, and in certain loops, it's very useful to me to be able to do increment chars, and index arrays by chars.
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How do I remove all non alphanumeric characters from a string except dash?
How do I remove all non alphanumeric characters from a string except dash and space characters?
13 Answers
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Turn a string into a valid filename?
I have a string that I want to use as a filename, so I want to remove all characters that wouldn't be allowed in filenames, using Python.
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Get first n characters of a string
How can I get the first n characters of a string in PHP? What's the fastest way to trim a string to a specific number of characters, and append '...' if needed?
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Base64 length calculation?
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Each character is used to represent 6 bits (log2(64) = 6).
Therefore 4 chars are used to represent 4 * 6 = 24 bits = 3 bytes.
So you need 4*(n/3) chars to represent n bytes, and this needs to be rounded up to a multiple of 4.
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How do I duplicate a whole line in Emacs?
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which breaks down to
C-a: move cursor to start of line
C-SPACE: begin a selection ("set mark")
C-n: move cursor to next line
M-w: copy region
C-y: paste ("yank")
The aforementioned
C-a C-k C-k C-y C-y
amounts to the same thing (TMTOWTDI)
C-a: move cursor to start of line
C-k: cut ("kill") ...