Untitled

In this post i will explain how to calculate reverse of the given number.Suppose given number is 234.Then what will be the reverse of this given number?

Answer is 432.

It is easy to find out the reverse of any given number using pen and paper, but if you want to calculate the reverse using a program then how will you write the program.

Lets think about it, if we want to reverse any number then…

How HashMap works in Java?

It is a simple answer,it works on the principle of hashing.In HashMap elements are stored in pair of (key,value) and also we can fetch the value in constant time O(1) provided we know the key.We store objects in HashMap using put(key,value) and retrieve value using get(key) which returns value.

Working of put(key,value):When we want to add a element in the HashMap,we…