Recursion in computer science is a method of problem solving where the solution to a problem depends on solutions to smaller instances of the same problem.
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Recursive Tic-Tac-Toe Solver in Python
I'm implementing a Tic-Tac-Toe solver in Python. It contains two functions: assess to determine whether a given board position is a win for either side, and ...
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Counting Increasing Subsequences of size K recursive
The original description of the problem can be found here, its input here and its expected output here.
The problem:
Given a integer sequence a1 ... an (-10000
\$\leq\$ ai \$\leq\$ 10000). ...
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Simple recursive function to find missing number in a permutation
This is a short and simple Python written to help me sharpen my dulling recursion skills. It expects a sorted permutation of integers n1..n2 in list format, with a single step missing (e.g., ...
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3answers
117 views
Reversing strings using recursion
I'm trying to solve exercises where I am required to use recursion. I wrote this:
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2answers
79 views
Beginner implementation of Merge Sort
This is my first time implementing a merge sort (just getting started with algorithms & data structures).
Are there any obvious things I have done wrong?
I am also worried that I have overused ...
4
votes
1answer
57 views
Merge sort implementation in JS
Just for learning and practicing I've created a completely recursive version of the merge sort algorithm.
I've tested it a little bit and it seems working, but I'm quite sure that it can be largely ...
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5answers
148 views
Permutation of n lists
I have code which gives permutations for 10 lists. The code works fine for small number of lists with small number of values.
Result : It should return all possible permutations. I have to store the ...
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1answer
39 views
Practicing recursion with getElementsByClassName
I'm trying to get a good grasp on recursion by implementing document.getElementsByClassName. I've made something that works but I'd like to know if there is some ...
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2answers
31 views
Inserting new Node in a Binary Search Tree
I wrote this method to recursively insert a new node at the proper position in a BST. Is it good enough? Can it be improved? It went through a couple of revisions and I still am not very confident in ...
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0answers
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Selecting subset of size k using recursion
Sometimes I need to implement recursive algorithms that pass a certain state from one recursive call to another. For example, a greedy subset selection: we have a set of candidate objects, and we ...
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2answers
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Generate URLs from a complex JSON object using recursion
My task is here as follows :
Input : A complex/nested JSON object with nested arrays as well
objects
Output : A JSON object that contains a set of URLs with their titles:
( key,value ) ...
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votes
1answer
51 views
Recursive Sudoku Solver
I just finished up a program which takes a byte[9][9] as input and recursively does a DFS to find any solutions (including multiple solutions). I'm pretty happy ...
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1answer
31 views
Recursively delete empty folders in Lua
I have written a script that run in WingFTP Server which has a Lua scripting engine built in. The script recursively deletes empty folders except the specified root folder.
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2answers
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Recursively evaluate neighbors in a two dimensional grid
I'm creating a puzzle mini game where there is a board of gems, varying in color, and chosen at random.
This is what my code generates:
When you click on a gem the game should traverse the board ...
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1answer
65 views
Combining two sorted lists
I'm just hoping if there's a way to simplify this recursive code that takes 2 sorted lists and combines the two together in a sorted manner (without actually having to re-sort them).
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2answers
335 views
Recursively insert a node in an ordered Linked List
I've written this and it works great. Is there any shorter or simpler way to achieve the same result without distinguish between cases?
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0answers
59 views
Find the most efficient combination that equals target number in ArrayList
I want to implement the following function:
Given a target sum, return the combination that equals the target sum and is the most efficiënt combination in the array of an ...
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1answer
57 views
Creating a menu as nested unordered lists from JSON data
I have a JSON input using which I have written below function to recursively create an unordered list.
Is there more precise way to achieve it?
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2answers
35 views
Tail-Recursion to get a Map of word counts
I want to read a file and store the number of occurrences of each word in a Map, using tail recursion. I came up with the following; it seems to work; does it look like it's right?
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2answers
54 views
Algorithm that checks if a tree is full and complete
I am trying to write a method that will return true if a binary tree is full and complete (each node has 2 children or none and all the leaves of the tree are at the same depth).
My idea is to use ...
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164 views
Let's Break Down the Party by Breaking the Party Down Recursively
This is a rags-to-riches an overdue alternative implementation on my previous question: Let's Break Down the Party
This alternative uses the int internal ...
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votes
1answer
29 views
Adding a node to a Binary Search Tree and printing the path to it
I wrote BST insertion code with the book. The book uses recursion, but I just want to know how I can do it without recursion.
My code is working, but I don't know if it is correct.
...
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votes
3answers
226 views
Using recursion to count substrings (with exceptions to the rule) in Java
I am going through the CodingBat exercises for Java. Here is the one I have just finished:
Given a string, compute recursively the number of times lowercase hi ...
5
votes
1answer
80 views
Test file word cloud in F#
This code is meant to take in a command line argument and output a 'tag cloud'. It's more of an exercise in learning F# for me because this is my first non-tutorial code file. How could this code be ...
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2answers
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Basic functions (sum, len, etc.) with recursively-flattened arguments
Based on the excellent answers provided for my previous question, I've thoroughly revised my attempt at "deep" versions of all, ...
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2answers
116 views
Consecutive Primes challenge at CodeEval.com and memory allocation issue
I finally solved this challenge with using recursion and figured out why the automatic scorer wasn't passing my previous solutions. I was using NSMutableArray to ...
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votes
0answers
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Recursive flattening of Swift sequences
In Flatten to get all child controls of certain type in a UIView, methods were discussed to
recursively flatten a tree-like structure in Swift, resulting in an array
of all elements.
Motivated by ...
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votes
1answer
40 views
Palidrome checker in haskell
I decided to avoid the trivial isPalindrome lst = lst == reverse lst and tried writing a method with pattern matching and recursion.
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3answers
381 views
Deep/recursive join, all, any, sum, len
I keep forgetting that the standard join() can only take a single iterable, so I made a few functions that act recursively on any passed arguments. Somewhat ...
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2answers
191 views
Recursive math expression eval
It has been very hard to use recursion, but I think that it made the code shorter and cleaner.
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0answers
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Recursive way to find Inorder successor
So far I have attempted to find the inorder successor through recursion and it seems to be working right. Can someone review the below code and give suggestions.
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1answer
60 views
Is this the best way to check sorting (in recursion) without loops?
Please let me know if there is a shorter way to do it again without any kind of loops. Recursion only.
...
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2answers
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Print the nodes of binary tree column-wise, using recursion and iteration
I am trying to code for both recursive and iterative approach to a problem.
Below is a recursive code to print the nodes of binarytree column wise. Basically I have count of root as 0 and if I move ...
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votes
3answers
115 views
Directory Snapshot
The following code creates a recursive backup of a directory in the form of interlinked HTML files, structured in the same form as the input directory.
It does not take the backup of the contents ...
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vote
2answers
61 views
Forming combinations of a 16 bit binary number
I wrote this code to form combinations of a 16 bit binary number (I know it is in output is string format, but it is my goal to just print all possible 16 bit binary numbers). My question is, can this ...
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votes
2answers
44 views
Recursive file copy function
I created this function and I'm unsure if it is sufficient for "real world use", because all code snippets on the net I found for recursive copy functions used functions like
...
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1answer
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Arranging 8 queens on an 8x8 board
Print all the ways of arranging eight queens on an 8x8 board. Rules:
Queens should not share the same row, column, of any diagonal.
Any comment on my solution?
I didn't write unit tests but I ...
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votes
2answers
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A set of names and a request with asterisks
I have a set of names and a request with asterisks. An asterisk can be replaced with any letter.
For example, there is a set of names: hasad, ahmed, fizo. And there are a few sample requests: hasad, ...
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votes
2answers
410 views
Non-recursive method for finding a ^ n
I am working on an interview question from Amazon Software. The particular question I am working on is "to write a program to find an."
Here is my recursive solution to this problem (in Java):
...
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2answers
331 views
Using recursion to count nodes in a binary tree, test equality of linked lists, and find extrema of a linked list
I am working with a some small functions to test recursion. I am fairly new to Python and am wondering if there is a cleaner way to get the job done.
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1answer
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Grid walk problem and solving it recursively
On CodeEval, there's a Grid Walk challenge:
There is a monkey which can walk around on a planar grid. The monkey can move one space at a time left, right, up or down. That is, from (x, y) the ...
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2answers
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Recursive Brute-Force [closed]
I have to recursively solve the following problem, using a brute force approach:
Suppose two people, A and B, have an even number of ordered boxes, each with a given value. For example, ...
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votes
3answers
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Condensing code that generates Pascal's triangle
I recently started learning Java for a class and my teacher gave us an assignment in which we had to write up code which would print out the Pascal's triangle to an amount of rows decided by the user, ...
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votes
2answers
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Given a digit sequence, print the possible decodings of the given digit sequence
Examples:
12 gives:
'AB' and 'L'
and
123 gives
'ABC', 'LC' and 'AW'
Here is my attempt:
...
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2answers
140 views
Recursive functions for sorting
I made a few recursive functions for learning purposes which do a variety of tasks. Here is my current and functioning code:
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4answers
2k views
To understand what recursion is, you must first understand recursion
This is the second assignment for my CS2 course:
Write a recursive C++ function writeLine() that writes a character repeatedly to form a line of n ...
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votes
1answer
129 views
Paint fill function
Implement the "paint fill" function of image editing programs: Given a
screen point and new color fill the surrounding area.
Any comments on the code below?
Time complexity: ...
