## C code for Radix Tree (or Trie)

A Trie is a very useful (but often ignored) data structue, which can be used to solve a large number of Strings related problems quickly. In terms of Time and Space complexity, following are the 2 main properties of Trie: Trie uses a Symbol Table approach (a Hash Map) like data structure for reducing the […]

## C Code for Binary Search Tree Traversal

A Binary Search Tree is a Binary Tree datastructure (a tree in which each node has at most two children) which has the following properties: The left subtree of a node contains only nodes with keys less than the node’s key. The right subtree of a node contains only nodes with keys greater than the […]

## Sorting Objects Using Comparable in java

So, sorting is a snap in Java – just use any Collection to store your objects and then just call Collections.sort(List<T>); which will internally call Arrays.sort(Object[] a); which eventually will use mergeSort. Source Code of Collections.sort(List) But, how will Java know, while sorting, how to compare different objects ? So for this, it uses Comparable […]

## Java code for Permutation using Steinhaus–Johnson–Trotter algorithm

Steinhaus–Johnson–Trotter algorithm is an efficient algorithm to find the permutations of a set of entities. The code given here use Even’s speedup to improve the running time of the algorithm by storing additional information for each element in the permutation: its position, and a direction (positive or negative) in which it is currently moving. The […]

## Stanford Computer Scientists Find Internet Security Flaw

Stanford University researchers have found a security flaw in audio-based completely automated public Turing test to tell computers and humans apart (CAPTCHAs), which are designed to provide Internet security for the visually impaired. Audio CAPTCHAs require users to listen to a string of spoken letters or numbers disguised with background noise. However, Stanford professor John […]