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Math.random() versus Random.nextInt(int)
What is the difference between Math.random() * n and Random.nextInt(n) where n is an integer?
4 Answers
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Why java.io.File doesn't have a close() method?
While java.io.RandomAccessFile does have a close() method java.io.File doesn't. Why is that? Is the file closed automatically on finalization or something?
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What are the differences between a clustered and a non-clustered index?
What are the differences between a clustered and a non-clustered index ?
12 Answers
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~x + ~y == ~(x + y) is always false?
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Assume for the sake of contradiction that there exists some x and some y (mod 2n) such that
~(x+y) == ~x + ~y
By two's complement*, we know that,
-x == ~x + 1
<==> -1 == ~x + x
Noting this result, we have,
~(x+y) == ~x + ~y
<==> ~(x+y) + (x+y) == ~x + ~y...
How to open a web server port on EC2 instance
...to the "Network & Security" -> Security Group settings in the left hand navigation
Find the Security Group that your instance is apart of
Click on Inbound Rules
Use the drop down and add HTTP (port 80)
Click Apply and enjoy
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How to convert URL parameters to a JavaScript object?
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Edit
This edit improves and explains the answer based on the comments.
var search = location.search.substring(1);
JSON.parse('{"' + decodeURI(search).replace(/"/g, '\\"').replace(/&/g, '","').replace(/=/g,'":"') + '"}')
Example
Parse abc=foo...
Gradle to execute Java class (without modifying build.gradle)
There is simple Eclipse plugin to run Gradle, that just uses command line way to launch gradle.
4 Answers
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NameError: name 'reduce' is not defined in Python
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The previous user has already answered the question and the answer is same as that of his answer
– Kathiravan Natarajan
Jul 24 '17 at 1:28
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Add unique constraint to combination of two columns
I have a table and, somehow, the same person got into my Person table twice. Right now, the primary key is just an autonumber but there are two other fields that exist that I want to force to be unique.
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Rails detect if request was AJAX
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Warning: this does not work on standard remote: true calls in newer Rails versions, as the necessary headers don't get set.
– Roland Studer
May 27 at 18:04
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