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Grep characters before and after match?
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3 characters before and 4 characters after
$> echo "some123_string_and_another" | grep -o -P '.{0,3}string.{0,4}'
23_string_and
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Why should eval be avoided in Bash, and what should I use instead?
Time and time again, I see Bash answers on Stack Overflow using eval and the answers get bashed, pun intended, for the use of such an "evil" construct. Why is eval so evil?
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What is the significance of initializing direction arrays below with given values when developing ch
I am new to competitive programming, and I noticed frequently, many of the great coders have these four lines in their code (particularly in those involving arrays):
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How does the C code that prints from 1 to 1000 without loops or conditional statements work?
...prints from 1 to 1000 without loops or conditionals :
But I don't understand how it works. Can anyone go through the code and explain each line?
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Fast permutation -> number -> permutation mapping algorithms
...you have n possibilities, so you can describe this with a number between 0 and n-1. For the position that the next element ends up at, you have n-1 remaining possibilities, so you can describe this with a number between 0 and n-2.
Et cetera until you have n numbers.
As an example for n = 5, consid...
SQL JOIN and different types of JOINs
What is a SQL JOIN and what are different types?
6 Answers
6
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CPU Privilege Rings: Why rings 1 and 2 aren't used?
...the modern protection model) only has a concept of privileged (ring 0,1,2) and unprivileged, the benefit to rings 1 and 2 were diminished greatly.
The intent by Intel in having rings 1 and 2 is for the OS to put device drivers at that level, so they are privileged, but somewhat separated from the r...
What values should I use for CFBundleVersion and CFBundleShortVersionString?
This is my first iOS app submission and I don't want my app rejected.
7 Answers
7
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“Conversion to Dalvik format failed with error 1” on external JAR
In my Android application in Eclipse I get the following error.
71 Answers
71
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Delete topic in Kafka 0.8.1.1
... Thanks for the info. Do you know how to clear the entire Kafka and Zookeeper states as indicated?
– EmPak5
Jun 18 '14 at 16:09
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