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Execution time of C program
I have a C program that aims to be run in parallel on several processors. I need to be able to record the execution time (which could be anywhere from 1 second to several minutes). I have searched for answers, but they all seem to suggest using the clock() function, which then involves calculating...
Android: upgrading DB version and adding new table
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1. About onCreate() and onUpgrade()
onCreate(..) is called whenever the app is freshly installed. onUpgrade is called whenever the app is upgraded and launched and the database version is not the same.
2. Incrementing the db version
You need a constructor like:
MyOpenHelp...
What is the “__v” field in Mongoose
... now, but I wanted something that I could put in the Schema directly so in all queries.
– diosney
Mar 24 '14 at 11:52
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How to parse/read a YAML file into a Python object? [duplicate]
...ame: Node 2
branch2-1:
name: Node 2-1
And you've installed PyYAML like this:
pip install PyYAML
And the Python code looks like this:
import yaml
with open('tree.yaml') as f:
# use safe_load instead load
dataMap = yaml.safe_load(f)
The variable dataMap now contains...
What is a practical use for a closure in JavaScript?
...rating instrumentation (counting calls) from semantics (an error-reporting API). Other uses include:
Passing parameterised behaviour into an algorithm (classic higher-order programming):
function proximity_sort(arr, midpoint) {
arr.sort(function(a, b) { a -= midpoint; b -= midpoint; return a*...
Are duplicate keys allowed in the definition of binary search trees?
...cluded. For example, the example algorithms in the MIT Algorithms book usually present examples without duplicates. It is fairly trivial to implement duplicates (either as a list at the node, or in one particular direction.)
Most (that I've seen) specify left children as <= and right children ...
Syntax Error: Not a Chance
...ng blocks by braces instead of indentation will never be implemented.
Normally, imports from the special __future__ module enable features that are backwards-incompatible, such as the print() function, or true division.
So the line from __future__ import braces is taken to mean you want to enable ...
Best algorithm for detecting cycles in a directed graph [closed]
What is the most efficient algorithm for detecting all cycles within a directed graph?
14 Answers
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Efficient Algorithm for Bit Reversal (from MSB->LSB to LSB->MSB) in C
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NOTE: All algorithms below are in C, but should be portable to your language of choice (just don't look at me when they're not as fast :)
Options
Low Memory (32-bit int, 32-bit machine)(from here):
unsigned int
reverse(register ...
How do I expire a PHP session after 30 minutes?
...ms with filesystems where atime tracking is not available.
So it additionally might occur that a session data file is deleted while the session itself is still considered as valid because the session data was not updated recently.
And second:
session.cookie_lifetime
session.cookie_lifetime ...