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What is pseudopolynomial time? How does it differ from polynomial time?
...r of bits required to represent W
i.e. size of input= s =log(W) (log= log base 2)
-> 2^(s)=2^(log(W))
-> 2^(s)=W (because 2^(log(x)) = x)
Now, running time of knapsack= O(nW) = O(n * 2^s)
which is not polynomial.
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find() with nil when there are no records
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Yes, just do:
Challenge.find_by_id(10)
For Rails 4 and 5:
Challenge.find_by(id: 10)
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Convert string with commas to array
...ols: like e.g. "0,s" any ideas how to fix that?
– sqp_125
Aug 31 '17 at 12:48
1
@sqp_125 try 0,'s...
When should I choose Vector in Scala?
...t your algorithm is doing.
List is a singly linked list, while Vector is a base-32 integer trie, i.e. it is a kind of search tree with nodes of degree 32.
Using this structure, Vector can provide most common operations reasonably fast, i.e. in O(log_32(n)). That works for prepend, append, update, ra...
Pip freeze vs. pip list
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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Reducing the space between sections of the UITableView
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Why not use CGFLOAT_MIN? It's made for these kind of scenarios :)
– Andrei Filip
May 11 '15 at 9:38
12
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How to prevent robots from automatically filling up a form?
...ow to track this time without cookies requires some way of server-side database. This may be an impact in performance.
Also you need to tweak the threshold-time.
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DateTime.ToString() format that can be used in a filename or extension?
...our file name.
Here i have provided example
string fileName = "fileName_" + DateTime.Now.ToString("MM-dd-yyyy_hh-mm-ss-tt") + ".pdf";
OR
If you don't prefer to use symbols you can try this also.,
string fileName = "fileName_" + DateTime.Now.ToString("MMddyyyyhhmmsstt") + ".pdf";
Hope this ...
How to check which version of v8 is installed with my NodeJS?
... version (don't know since when this is available)
> npm version
{ http_parser: '1.0',
node: '0.10.35',
v8: '3.14.5.9',
ares: '1.9.0-DEV',
uv: '0.10.30',
zlib: '1.2.8',
modules: '11',
openssl: '1.0.1j',
npm: '1.4.28',
xsjs: '0.1.5' }
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Importing a Swift protocol in Objective-C class
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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