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How do you set, clear, and toggle a single bit?
How do you set, clear, and toggle a bit?
30 Answers
30
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Way to get number of digits in an int?
...thematically, numbers don't have a length, nor do they have digits. Length and digits are both properties of a physical representation of a number in a specific base, i.e. a String.
A logarithm-based solution does (some of) the same things the String-based one does internally, and probably does so ...
How does Java handle integer underflows and overflows and how would you check for it?
How does Java handle integer underflows and overflows?
12 Answers
12
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Reference: mod_rewrite, URL rewriting and “pretty links” explained
...plained. mod_rewrite is one way to make "pretty links", but it's complex and its syntax is very terse, hard to grok, and the documentation assumes a certain level of proficiency in HTTP. Can someone explain in simple terms how "pretty links" work and how mod_rewrite can be used to create them?
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What's the difference between echo, print, and print_r in PHP?
I use echo and print_r much, and almost never use print .
11 Answers
11
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How to output only captured groups with sed?
...as well as specifying what you do want.
string='This is a sample 123 text and some 987 numbers'
echo "$string" | sed -rn 's/[^[:digit:]]*([[:digit:]]+)[^[:digit:]]+([[:digit:]]+)[^[:digit:]]*/\1 \2/p'
This says:
don't default to printing each line (-n)
exclude zero or more non-digits
include on...
What's the difference between tilde(~) and caret(^) in package.json?
After I upgraded to latest stable node and npm , I tried npm install moment --save . It saves the entry in the package.json with the caret ^ prefix. Previously, it was a tilde ~ prefix.
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ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.al
...ch was causing all sorts of problems. I was inadvertently doing a bitwise AND instead of a logical AND .
6 Answers
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Returning a boolean from a Bash function
... want to write a bash function that check if a file has certain properties and returns true or false. Then I can use it in my scripts in the "if". But what should I return?
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How is a CRC32 checksum calculated?
... + x8 + x7 + x5 + x4 + x2 + x + 1
Wikipedia
CRC calculation
Or in hex and binary:
0x 01 04 C1 1D B7
1 0000 0100 1100 0001 0001 1101 1011 0111
The highest term (x32) is usually not explicitly written, so it can instead be represented in hex just as
0x 04 C1 1D B7
Feel free to count...