I simplified the test a bit – if all(x%y instead of if not any(not x%y I also limited y’s range; there is no point in testing for divisors > sqrt(x). So max(x) == 100 implies max(y) == 10. For x <= 10, y must also be < x. Instead of generating pairs of primes and … Read more
Try square brackets: i.e.: use an list instead of a set
Use the retainAll() method of Set: If you want to preserve the sets, create a new set to hold the intersection: The javadoc of retainAll() says it’s exactly what you want: Retains only the elements in this set that are contained in the specified collection (optional operation). In other words, removes from this set all of its elements that are not contained in the … Read more
You can create a set of tuples, a set of lists will not be possible because of non hashable elements as you mentioned.
Take a look at LinkedHashSet class From Java doc: Hash table and linked list implementation of the Set interface, with predictable iteration order. This implementation differs from HashSet in that it maintains a doubly-linked list running through all of its entries. This linked list defines the iteration ordering, which is the order in which elements were inserted into the … Read more
Take a look at LinkedHashSet class From Java doc: Hash table and linked list implementation of the Set interface, with predictable iteration order. This implementation differs from HashSet in that it maintains a doubly-linked list running through all of its entries. This linked list defines the iteration ordering, which is the order in which elements were inserted into the … Read more
Use frozenset, To represent a set of sets, the inner sets must be frozenset objects for the reason that the elements of a set must be hashable (all of Python’s immutable built-in objects are hashable). frozenset is immutable and set is mutable.
The individual items that you put into a set can’t be mutable, because if they changed, the effective hash would change and thus the ability to check for inclusion would break down. Instead, you need to put immutable objects into a set – e.g. frozensets. If you change the return statement from your enum method to… …then it … Read more
he typical way to check for existence in many STL containers such as std::map, std::set, … is:
The Python itertools page has exactly a powerset recipe for this: Output: If you don’t like that empty tuple at the beginning, you can just change the range statement to range(1, len(s)+1) to avoid a 0-length combination.