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What is pseudopolynomial time? How does it differ from polynomial time?
...ng TSP takes time O(n · n!), which isn't polynomial time.
These runtimes all refer to some variable n that tracks the size of the input. For example, in selection sort, n refers to the number of elements in the array, while in TSP n refers to the number of nodes in the graph. In order to standardi...
How do I break out of a loop in Scala?
...nt) {
sum += i; if (sum < max) addTo(i+1,max)
}
addTo(0,1000)
(1c) Fall back to using a while loop
var sum = 0
var i = 0
while (i <= 1000 && sum <= 1000) { sum += 1; i += 1 }
(2) Throw an exception.
object AllDone extends Exception { }
var sum = 0
try {
for (i <- 0 to 1...
Match everything except for specified strings
...
Depends on the language, but there are generally negative-assertions you can put in like so:
(?!red|green|blue)
(Thanks for the syntax fix, the above is valid Java and Perl, YMMV)
share
...
How to write to an existing excel file without overwriting data (using pandas)?
...omething like this might work out:
import pandas
from openpyxl import load_workbook
book = load_workbook('Masterfile.xlsx')
writer = pandas.ExcelWriter('Masterfile.xlsx', engine='openpyxl')
writer.book = book
## ExcelWriter for some reason uses writer.sheets to access the sheet.
## If you leave ...
What do parentheses surrounding an object/function/class declaration mean? [duplicate]
... useful construct when trying to hide variables from the parent namespace. All the code within the function is contained in the private scope of the function, meaning it can't be accessed at all from outside the function, making it truly private.
See:
http://en.wikipedia.org/wiki/Closure_%28comput...
IntelliJ inspection gives “Cannot resolve symbol” but still compiles code
...
First of all you should try File | Invalidate Caches and if it doesn't help, delete IDEA system directory. Then re-import the Maven project and see if it helps.
In some weird cases compiled classes may report wrong info and confuse I...
Composer: how can I install another dependency without updating old ones?
I have a project with a few dependencies and I'd like to install another one, but I'd like to keep the others the way they are. So I've edited the composer.json , but if I run composer install , I get the following output:
...
Exit codes in Python
...
What you're looking for in the script is calls to sys.exit(). The argument to that method is returned to the environment as the exit code.
It's fairly likely that the script is never calling the exit method, and that 0 is the default exit code.
...
How to emulate C array initialization “int arr[] = { e1, e2, e3, … }” behaviour with std::array?
...s question is about not having to specify the number of elements and still allow nested types to be directly initialized.)
This question discusses the uses left for a C array like int arr[20]; . On his answer , @James Kanze shows one of the last strongholds of C arrays, it's unique initializat...
Understanding NSRunLoop
... run loop directly, though there are some (networking) components that may allow you to specify which run loop they will use for I/O processing.
A run loop for a given thread will wait until one or more of its input sources has some data or event, then fire the appropriate input handler(s) to proce...