Sort elements by frequency
Problem: Sort elements by frequency. Sort elements of an array by frequency of the elements of the array. Sort the elements by decreasing order of their frequency. If two …
Stack implementation using array in Java
Objective: Stack implementation using array. To implement a stack which can be used with any data type. In this article we will see how to implement a stack using …
Find first duplicate character in a string in Java
Problem: Write a Java program to find first duplicate character in a string. For example: If given string is color, then the first duplicate character in the string is …
Reverse words in a string in Java
Problem: Write a Java program to reverse words in a string. For example: Input sentence : Java fries is an awesome site for programming questions Output: questions programming for site …
First non repeating character in a string in Java
Problem: Write a Java program to find first non repeating character in a string or first unique character in a string. For example. 1. In string “baby”, first non repeating …
Check if a given array contains duplicate elements within k distance from each other
Problem: Write a Java program to check if a given unsorted array contains duplicate elements within k distance from each other. For example: If k = 3 and array is …
Java program for Fibonacci series
Problem: Write a Java program to print Fibonacci series. Here we have to print first ‘n’ numbers of Fibonacci series. This is a college level program and could be asked …
Difference between abstract class and interface in Java
In this article we will see the difference between abstract class and interface. This is famous interview question. You might have come across this question when you gave your …
Duplicate elements in array in Java
Problem: Write a Java program to find duplicate elements in array. This is entry-level interview question and interviewers are interested to see if you can solve the problem with …
Second largest number in an array
Problem: Find the second largest number in an array. This program is asked in entry-level interviews. In this article we will see how to find second largest number in array in …