Skip to main content
The 2025 Developer Survey results are in. Explore insights into technology and tools, careers, community and more. View results.

All Questions

Filter by
Sorted by
Tagged with
7 votes
2 answers
6k views

Permutations with replacement in Python

Many a times, I've had the need to use a permutations with replacement function. So, I've written a function to do just that: ...
Sriv's user avatar
  • 2,800
3 votes
2 answers
291 views

Fixed Content Necklace Generator

I wrote a class that generates combinatorial necklaces with fixed content as per Sawada: A fast algorithm to generate necklaces with fixed content. The class is instantiated with an input list that ...
Rek's user avatar
  • 33
4 votes
3 answers
553 views

Generate parentheses solution

I have coded a solution to build all valid permutations of parentheses. My code is below. I have a question on my code based on a comment by my PEP8 checker. It said that there was no need to ...
MrJoe's user avatar
  • 2,143
4 votes
1 answer
4k views

Recursive implementation of power set in Python

I was doing a recursion problem called power set, and would like to get code review. Here's the problem. ...
NinjaG's user avatar
  • 2,559
3 votes
1 answer
254 views

python magic square finder for arbitrary numbers

I wrote this code to get all possible magic squares that can be made with a list you put in. The only contraints are that the count of numbers is a square and that each number is unique. It even works ...
Tweakimp's user avatar
  • 779
2 votes
1 answer
9k views

Computing the powerset of a list

I've written the following code for computing the powerset of a list (we consider the list has all distinct elements, although it doesn't really matter). Can this function be further optimized? <...
Hisoka Moroh's user avatar
4 votes
1 answer
3k views

K-combination recursive algorithm implementation

Tried to implement this solution for finding n choose k. I have used recursion and this is how it goes for k as 4 and n as 6. Zero based The idea is to have array of size k keeping sequence of ...
newbie_old's user avatar
6 votes
2 answers
7k views

Making the same amount from different combinations of coins (top-down approach)

I was reading a typical interview question found here. Given an amount and a list of denominations, count the number of possible ...
under_the_sea_salad's user avatar
4 votes
1 answer
427 views

Counting ways to fit bottles in crates

I'm calculating how many possibilities there are to fit \$n\$ identical bottles inside \$k\$ crates of various capacities. n = Number of bottles k = Number of crates K = List of the number of bottles ...
Deniz Alz's user avatar
8 votes
1 answer
983 views

Recursive search for combinations of words that have a specified MD5 hash

This code solves a challenge problem that a local company is hosting to attract/screen applicants. The link to the challenge is here. In brief, we are given a wordlist containing approximately 100,...
Charles Harris's user avatar
4 votes
4 answers
9k views

Staircase problem solved using recursion

Problem Question taken from here. I want to go up a flight of stairs that has n steps. I can either take 1 or 2 steps each time. How many different ways can I go up this flight of stairs? Write a ...
overexchange's user avatar
  • 3,401
2 votes
1 answer
3k views

Insect combinatorics challenge

Below is the problem taken from Berkeley's Cs61A page here Question 9: Insect Combinatorics* Consider an insect in an M by N grid. The insect starts at the bottom left corner, (0, 0), and wants ...
overexchange's user avatar
  • 3,401
2 votes
2 answers
1k views

Count the number of combinations with gap-restriction for every pair of values

A lottery draw consists of choosing 6 different values from 1 to 50. I want to calculate the number of combinations with gaps of at least 3 between every pair of values. I have used the following ...
barak manos's user avatar
  • 1,243
2 votes
1 answer
6k views

Nsum problem: find all n elements in an array whose sum equals a given value

I am pretty new to Python, so I want to listen to any advice that improve my coding style in a "pythonic" way, even about naming style of variables. The following code reflects a very general paradigm ...
Fashandge's user avatar
  • 123