All Questions
13 questions
2votes
1answer
50views
Optimal Extraction of Longest Sorted Sequence from Individually Sorted Bucket Arrays Without Repetitions
Consider a bucket array containing sorted and/or empty buckets, and the goal is to extract the longest possible sequence in sorted order, under the following conditions: Only one element in each ...
- 121
3votes
1answer
231views
Killing a Hydra - Overengineered
Background This question is inspired by the question: Killing a hydra, and my response therein. I will restate the problem at hand in full so that this question is fully self contained You can only ...
- 5,745
6votes
3answers
1kviews
Minimum path sum in a triangle (Project Euler 18 and 67) with Python
Project Euler 18 Project Euler 67 As problem 67 is harder, I'll go with that one: By starting at the top of the triangle below and moving to adjacent numbers on the row below, the maximum total ...
- 2,790
1vote
1answer
282views
Project Euler # 21 amicable numbers Python
Let \$d(n)\$ be defined as the sum of proper divisors of \$n\$ (numbers less than \$n\$ which divide evenly into \$n\$). If \$d(a) = b\$ and \$d(b) = a\$, where \$a ≠ b\$, then \$a\$ and \$b\$ are an ...
user203258
6votes
2answers
307views
Project Euler #14: Longest Collatz Sequence starting point
Problem statement: The following iterative sequence is defined for the set of positive integers: n → n/2 (n is even) n → 3n + 1 (n is odd) Using the rule above and starting with 13, we ...
user203258
4votes
1answer
633views
The Dungeon game
This is a Leetcode problem - The demons had captured the princess (P) and imprisoned her in the bottom-right corner of a dungeon. The dungeon consists of M x N rooms laid out in a 2D grid. Our ...
- 2,585
2votes
0answers
377views
Bursting Balloons
This is a Leetcode problem - Given n balloons, indexed from 0 to n-1. Each balloon is ...
- 2,585
1vote
3answers
1kviews
Subarray Sum Equals K
I've written a solution to the following leetcode problem: Given an array of integers and an integer k, you need to find the total number of continuous subarrays whose sum equals to k. Example ...
1vote
1answer
2kviews
Project Euler Problem 31 (Coin Sum)
I just finished Project Euler 31: Coin sums, which asks how many ways there are to make £2 using British coins (1p, 2p, 5p, 10p, 20p, 50p, £1, and £2). When I compared my code and the problem review'...
4votes
1answer
797views
Count ways to reach the n’th stair
I have solved Leetcode climbing-stairs problem which is stated as: There are n stairs, a person standing at the bottom wants to reach the top. The person can climb either 1 stair or 2 stairs at a ...
- 205
4votes
1answer
174views
Counting increasing subsequences with a "hacker's" Binary Index Tree
This is an \$O(n \sqrt n)\$ solution to the the following problem: Given a sequence, compute the number of non-empty increasing subsequences The algorithm is to compute ...
3votes
2answers
1kviews
Solution to Google Code Jam 2008 round 1C problem B
This is my solution to Google Code Jam 2008 round 1C problem B (Ugly Numbers). I think it's very elegant. However, I wonder if it's too concise. What could I improve here? The problem: Once upon a ...
4votes
3answers
3kviews
Project Euler 81 (minimum path sum through a matrix)
Problem Statement: In the 5 by 5 matrix below, 131 673 234 103 18 201 96 342 965 150 630 803 746 422 111 537 699 497 121 956 805 732 524 37 331 ...
- 5,190
