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How to check if a word is an English word with Python?
...
The same mention applies here too: a lot faster when converted to a set: set(words.words())
– Iulius Curt
Sep 30 '14 at 19:41
...
foreach with index [duplicate]
...ublic static void Each<T>(this IEnumerable<T> ie, Action<T, int> action)
{
var i = 0;
foreach (var e in ie) action(e, i++);
}
And use it like so:
var strings = new List<string>();
strings.Each((str, n) =>
{
// hooray
});
Or to allow for break-like behaviou...
How to get the user input in Java?
...ner;
//...
Scanner scan = new Scanner(System.in);
String s = scan.next();
int i = scan.nextInt();
BufferedReader and InputStreamReader classes
import java.io.BufferedReader;
import java.io.InputStreamReader;
//...
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String s ...
Extracting just Month and Year separately from Pandas Datetime column
...ore. Using df.my_date_column.astype('datetime64[M]'), as in @Juan's answer converts to dates representing the first day of each month.
– Nickolay
May 26 '18 at 19:52
4
...
Java's final vs. C++'s const
...e, later in Java only e.g.:
public class Foo {
void bar() {
final int a;
a = 10;
}
}
is legal in Java, but not C++ whereas:
public class Foo {
void bar() {
final int a;
a = 10;
a = 11; // Not legal, even in Java: a has already been assigned a value.
}
}
I...
Data structure: insert, remove, contains, get random element, all at O(1)
I was given this problem in an interview. How would you have answered?
14 Answers
14
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What is the performance cost of having a virtual method in a C++ class?
... class will have a virtual table, and every instance will have a virtual pointer.
9 Answers
...
Use of def, val, and var in scala
... Person) you are changing the age member variable.
And the last line:
println(person.age)
Here you are again calling the person method, which returns a new instance of class Person (with age set to 12). It's the same as this:
println(person().age)
...
Modern way to filter STL container?
...
See the example from cplusplus.com for std::copy_if:
std::vector<int> foo = {25,15,5,-5,-15};
std::vector<int> bar;
// copy only positive numbers:
std::copy_if (foo.begin(), foo.end(), std::back_inserter(bar), [](int i){return i>=0;} );
std::copy_if evaluates the lambda expr...
How to remove certain characters from a string in C++?
... string str("(555) 555-5555");
char chars[] = "()-";
for (unsigned int i = 0; i < strlen(chars); ++i)
{
// you need include <algorithm> to use general algorithms like std::remove()
str.erase (std::remove(str.begin(), str.end(), chars[i]), str.end());
}
// outpu...