How efficient/fast is Python’s ‘in’? (Time Complexity wise)
The complexity for lists is: O(n) For sets it is: O(1) http://wiki.python.org/moin/TimeComplexity
operator-keyword
c++ multiple definitions of operator
You’re breaking the one definition rule. A quick-fix is: inline ostream& operator<<(ostream& out, const CRectangle& r){ return out << “Rectangle: ” << r.x << “, ” << r.y; } Others are: declaring the operator in the header file and moving the implementation to Rectangle.cpp file. define the operator inside the class definition. . class CRectangle … Read more
Python AND operator on two boolean lists – how?
and simply returns either the first or the second operand, based on their truth value. If the first operand is considered false, it is returned, otherwise the other operand is returned. Lists are considered true when not empty, so both lists are considered true. Their contents don’t play a role here. Because both lists are … Read more
How do I create and use a class arrow operator? [duplicate]
The operator -> is used to overload member access. A small example: #include <iostream> struct A { void foo() {std::cout << “Hi” << std::endl;} }; struct B { A a; A* operator->() { return &a; } }; int main() { B b; b->foo(); } This outputs: Hi
Overloading operators in typedef structs (c++)
The breakdown of your declaration and its members is somewhat littered: Remove the typedef The typedef is neither required, not desired for class/struct declarations in C++. Your members have no knowledge of the declaration of pos as-written, which is core to your current compilation failure. Change this: typedef struct {….} pos; To this: struct pos … Read more
Haskell operator vs function precedence
Firstly, application (whitespace) is the highest precedence “operator”. Secondly, in Haskell, there’s really no distinction between operators and functions, other than that operators are infix by default, while functions aren’t. You can convert functions to infix with backticks 2 `f` x and convert operators to prefix with parens: (+) 2 3 So, your question is … Read more
Python: multiplication override
Just add the following to the class definition and you should be good to go: __rmul__ = __mul__
What does the operator |= do in JavaScript?
a[0] |= b is basically a[0] = a[0] | b “|” is an or bitwise operator Update When a[0] is assigned 0, a[0] in binary is 0000. In the loop, b = 0 a[0] = 0 (base 10) = 0000 (base 2) b = 0 (base 10) = 0000 (base 2) ————— a[0] | b … Read more
ternary operator without else in C
If you are using a ternary operator like that, presumably it could be replaced by: if (a) { b; } which is much, much better. (The intent is clearer, so the code is easier to read, and there will be no performance loss.) However, if you are using the ternary operator as an expression, i.e. … Read more
Operator == cannot be applied to ‘Long’ and ‘Int’ in Kotlin
Simply use long on your right side if (drawerItem.identifier == 1L) Edit: the reason this is required is that Kotlin does not promote Ints to Longs (or, more generally, does not widen types); on the left side we had a Long and on the right side we had an Int, which lead to the error. … Read more