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Algorithm to generate all possible permutations of a list?
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Basically, for each item from left to right, all the permutations of the remaining items are generated (and each one is added with the current elements). This can be done recursively (or iteratively if you like pain) until the last item is reach...
Count the number occurrences of a character in a string
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str.count(a) is the best solution to count a single character in a string. But if you need to count more characters you would have to read the whole string as many times as characters you want to count.
A better approach for this job would be:
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HTML input - name vs. id [duplicate]
...e two will not interfere with each other.
also, name can be used for more items, like when you are using radiobuttons. Name is then used to group your radiobuttons, so you can only select one of those options.
<input id="button_1" type="radio" name="option" />
<input id="button_2" type="r...
Parse large JSON file in Nodejs
...h returns a readable, object-mode stream that will receive the parsed data items, and is passed 3 arguments:
A readable stream containing the input JSON.
A predicate that indicates which items from the parsed JSON will be pushed to the result stream.
An options object indicating that the input is ...
Accessing dict_keys element by index in Python3
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Not a full answer but perhaps a useful hint. If it is really the first item you want*, then
next(iter(q))
is much faster than
list(q)[0]
for large dicts, since the whole thing doesn't have to be stored in memory.
For 10.000.000 items I found it to be almost 40.000 times faster.
*The fi...
What is Hindley-Milner?
...ge of the Hindley-Milner system is that each well-typed term has a unique "best" type, which is called the principal type. The principal type of the list-length function is "for any a, function from list of a to integer". Here a is a so-called "type parameter," which is explicit in lambda calculus...
Disable a group of tests in rspec?
...t this works, with both pending: and skip:, in rspec 3.6.0. Seems like the best solution to me. in rspec3 pending still runs tests, but skip does not (however you apply the skip).
– jrochkind
Jun 28 '18 at 14:41
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IEnumerable vs List - What to Use? How do they work?
... you to use the foreach syntax.
Basically it has a method to get the next item in the collection. It doesn't need the whole collection to be in memory and doesn't know how many items are in it, foreach just keeps getting the next item until it runs out.
This can be very useful in certain circumsta...
How do I iterate over the words of a string?
..., char delim, Out result) {
std::istringstream iss(s);
std::string item;
while (std::getline(iss, item, delim)) {
*result++ = item;
}
}
std::vector<std::string> split(const std::string &s, char delim) {
std::vector<std::string> elems;
split(s, delim, ...
Visual Studio warning: “Some of the properties associated with the solution could not be read”
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The best solution is to force the VS to regenerate the configs. To do this:
Open the sln file with a text editor.
Scroll down till you reach the last "EndProject" element.
Delete everything after that.
Save, Close and rebuild ...