recursion Questions

10

Solved

I'm trying to find whether a number is a power of 2 using recursion. However, I couldn't seem to figure out the correct solution. Here's what I've tried so far: def is_power(n): n = n/2 if n == ...
Puca asked 6/4, 2015 at 22:25

6

I'd like to write a function that deletes all empty folders, with the option to ignore certain file types (allowed file types are stored in the hashmap) and tell if it should look inside directorie...
Precondition asked 24/9, 2014 at 12:57

1

Solved

I want to declare a recursive function type (a function which declares itself) in C. In a language like Go I can do: type F func() F func foo() F { return foo } If I try to do the equivalent in ...
Snarl asked 25/1 at 0:44

7

Solved

I am currently optimizing a PHP application and found one function being called around 10-20k times, so I'd thought I'd start optimization there: function keysToLower($obj) { if (!is_object($obj) ...
Calefactory asked 5/6, 2010 at 18:7

2

Solved

in SICP Section 1.2.1 The author giving such a code example below to show how to using iterative process to solve the factorial problem: (define (factorial n) (fact-iter 1 1 n)) (define (fact-ite...
Blowbyblow asked 22/6, 2013 at 18:54

4

Solved

This regular expression matches palindromes: ^((.)(?1)\2|.?)$ Can't wrap my head around how it works. When does the recursion end, and when regex breaks from the recursive subpattern and goes to &q...
Warlike asked 26/7, 2012 at 13:14

2

My problem is like this: I have several lists need to be permuted, but the list numbers are unknowable. And every element numbers in every list are also unknowable. Sicne I would like to traverse ...
Fax asked 21/5, 2012 at 22:19

4

Solved

On the Bit Twiddling Hacks website the following algorithm is provided to round up an integer to the next power of two: unsigned int v; // compute the next highest power of 2 of 32-bit v v--; v |=...

10

Solved

I am trying to write a program that draws a sierpinski tree with python using turtle. Here is my idea: import turtle def draw_sierpinski(length,depth): window = turtle.Screen() t = turtle.Turtle...
Palaeontography asked 10/9, 2014 at 18:41

3

Solved

Need some help in creating function which can create folders recursively with giving path: C:\TestFolder\Another\AndAnother Delphi function MkDir returning IOerror = 3. MkDir('C:\TestFolder\Ano...
Munro asked 12/7, 2010 at 18:19

19

Solved

Given a set of numbers: {1, 3, 2, 5, 4, 9}, find the number of subsets that sum to a particular value (say, 9 for this example). This is similar to subset sum problem with the slight difference th...
Tuber asked 19/8, 2013 at 3:3

2

Solved

I looking for a suitable algorithm that will return the maximum depth of a collection of objects within a hierarchy of collections. I have a root object which may or may not contain a collection of...
Tole asked 9/3, 2023 at 16:57

5

Solved

This is just curiosity on my part, but what is more efficient, recursion or a loop? Given two functions (using common lisp): (defun factorial_recursion (x) (if (> x 0) (* x (factorial_recurs...
Bilharziasis asked 21/2, 2012 at 22:33

2

Solved

So given the following: def inorder(t): if t: inorder(t.left) yield t.key inorder(t.right) x = [ n for n in inorder(r) ] x only contains the root node, why? Here's the full code; note that...
Busily asked 22/4, 2015 at 13:50

8

Solved

I am trying to convert the keys of a multi-dimensional array from camelCase or StudlyCase/PascalCase to snake_case, with the added complication that some keys have a leading exclamation mark that I...
Mortgagor asked 18/9, 2009 at 13:14

10

Solved

I'm trying to recall an algorithm on Fibonacci recursion. The following: public int fibonacci(int n) { if(n == 0) return 0; else if(n == 1) return 1; else return fibonacci(n - 1) + fibonacci...
Framework asked 11/12, 2012 at 19:7

9

Solved

I'm trying to write a very simple function to recursively search through a possibly nested (in the most extreme cases ten levels deep) Python dictionary and return the first value it finds from the...
Cosenza asked 19/2, 2013 at 16:29

3

Solved

I wrote the follwing function: let str2lst str = let rec f s acc = match s with | "" -> acc | _ -> f (s.Substring 1) (s.[0]::acc) f str [] How can I know if the F# compiler turned it ...
Mollee asked 30/4, 2009 at 12:44

5

Solved

Good night everyone. I'm having trouble with probably some simple recursive function. The problem is to recursively list all files in a given folder and its subfolders. For the moment, I've m...
Bordelaise asked 1/5, 2018 at 18:32

5

I use GoogleColab to test data stuctures like chain-hashmap,probe-hashmap,AVL-tree,red-black-tree,splay-tree(written in Python),and I store very large dataset(key-value pairs) with these data...
Fortuity asked 20/2, 2018 at 6:56

1

I have a nested list called inputs: library(htmltools) library(shiny) inputs = tagList( selectInput('first', 'FIRST', letters), checkboxInput('second', 'SECOND') ) str(inputs, max.level = 1) ...
Tranquil asked 5/10, 2019 at 3:40

14

Solved

I have a dictionary like this: { "id": "abcde", "key1": "blah", "key2": "blah blah", "nestedlist": [ { "id": &q...
Heritor asked 21/3, 2012 at 15:26

8

Solved

For example: isin([1,2,3], [1,0,1,2,3,0]) will yield true because 123 is inside of 101230 I wrote the following code: isin([AH|AT],[AH|AT]). isin([AH|AT],[BH|BT]):- AH = BH, isin(AT,BT), isin([AH...
Feasible asked 13/8, 2011 at 15:31

8

Solved

I'm looking for something kind of like Object.keys but that works for potentially nested objects. It also shouldn't include keys that have object/array values (it should only include keys with imme...
Koan asked 1/11, 2017 at 20:12

10

I had an object like this (fields in snake_case) const obj = { vt_core_random: { user_details: { first_name: "xyz", last_name: "abc", groups: [ { id: 1, group_type: "EXT" }, { id: 2, g...
Glove asked 16/1, 2020 at 12:23

© 2022 - 2024 — McMap. All rights reserved.