All Questions
14 questions
9votes
2answers
1kviews
Implementation of Viterbi algorithm along with unit tests
Introduction to the Algorithm A system can be in N different, unobservable states, (i.e, we never know in which state the system actually is). The system also has a finite number of possible ...
- 1,655
3votes
3answers
461views
A tiny Java library for generating Gray codes
This library is for generating Gray codes. A Gray code over \$n\$ bits is a list of \$2^n\$ different \$n\$-bit strings subject to the following constraint: two adjacent bit string differ in only one ...
- 30.2k
6votes
1answer
127views
Benchmarking efficient inversion counting algorithms in Java
Given an array \$A = (a_1, a_2, \dots, a_n)\$, the number of inversions in \$A\$ is the number of index pairs \$i,j\$ (\$i < j\$) such that \$a_i > a_j\$. We can find the number of inversions in ...
- 30.2k
2votes
0answers
677views
A fast integer key map in Java via a van Emde Boas tree
Introduction The following data structure is a dictionary mapping primitive int values to any value type. Basically, under the hood it is a hash table, where a ...
- 30.2k
1vote
1answer
891views
Generic trie implementation in Java
I implemented a Trie data structure in Java, to test my understanding of the concept. I tried (pun intended :) ) to follow TDD steps along the way (i.e., add first a failing test case, and implement ...
- 1,655
4votes
1answer
208views
Algorithms to find various kinds of paths in graphs
I think many here are familiar with the graph data structure. Not very long ago, I implemented as an exercise a supposedly simple Graph application that does some traversals. To note, the most complex ...
- 251
7votes
3answers
873views
Nucleotide Count
I am learning Java and hence practicing it from here. The solution seems pretty trivial to me but still I would like to have a honest review which would guide me to following ideas: Am I maintaining ...
- 5,137
5votes
1answer
569views
Test whether target string is substring of source string
The code is self-explanatory. It has \$O(n)\$ complexity, and it tells whether a given string is the substring of the source string. Are there any cases where this algorithm fails? Is there anything ...
4votes
1answer
189views
Are AVL trees equal? - revision 3
The original question Given two binary trees, return true if they are structurally identical, and false otherwise. Are AVL trees equal? Are AVL trees equal? - revision 2 This revision on GitHub ...
- 1,369
1vote
1answer
189views
Are AVL trees equal? - revision 2
Revision 1. This revision on GitHub In addition to the solution itself, I wrote tests for all the possible cases. It seems you have verified all execution paths are covered. You are right. ...
- 1,369
8votes
1answer
774views
Are AVL trees equal?
I was inspired by this answer and decided to implement an AVL tree with the methods equals and hashCode as if I was asked to do ...
- 1,369
5votes
2answers
467views
Longest substring with unique characters
Find the length of the longest substring without repeating characters Any comments on my code? ...
- 177
3votes
2answers
2kviews
Radix sort with integer divisions
Here's a perhaps naive but simple implementation of Radix sort in Java. It works with any radix, and both positive and negative numbers. ...
- 112k
4votes
1answer
134views
TDD and use case: cook dish with substitutions
This is code for a class that takes available ingredients and returns left over ingredients after making a dish. Cesars: 2 carrot 4 ice burg 1 chicken 1 beans Russian: 2 carrots 2 beans 2 chicken If ...
- 223
