# Author: SJ

## Print all Unique elements in a given array

Objective: Given an array of integers which contains duplicates as well. Write a program to print all unique elements in the array. This problem is also referred as print all distinct elements in the...

## Multiply with power of 2 without using pow() or * operator

Objective: Given a number n and k, Calculate n * k2 without using pow() or *operator. Example: N = 3, k = 4 N*k2 = 48 Approach: Bit Manipulation Left shift the number N...

## Find Number of reverse pairs in an array

Objective: Given an array of integers A[],find no of reverse pairs means no of (i, j) pairs where i < j and A[i]>A[j]. Example: A[] = {10, 3, 4, 2, 5, 7, 9, 11}...

## Find first two largest elements in a given array

Objective: Given an array of integers, write an algorithm to find the first two largest elements in the array. Example: Int [] a = { 6, 8, 1, 9, 2, 1, 10}; Output: 10,...

## Calculate Logn base r – Java Implementation

Objective: Given a number n and r, write a program to calculate Logrn Example: N = 32, r =2 Log232= 5 N = 64, r = 4 Log464= 3 Approach: Without using built-In function-...

## Max Flow Problem – Introduction

Max Flow Problem- Maximum flow problems find a feasible flow through a single-source, single-sink flow network that is maximum. This problem is useful for solving complex network flow problems such as the circulation problem. The maximum value...

## Dijkstra Algorithm Implementation – TreeSet and Pair Class

Earlier we have seen what Dijkstra algorithm is is and how it works. In this article we will see its implementation using adjacency list and TreeSet. Example: Implementation – Adjacency List and Priority Queue...

## Java Program to find Sum the elements of an Array

Objective: Given an array of integers, write a java program to find the sum of all elements Example: Input [] = {20, 30, 40, 10, 5, 2, 60, 73} Output: 240 Approach: Do a...

## Insertion Sort – Java Implementation

What is Insertion Sort?? Insertion sort is a simple sorting algorithm that builds the sorted array one item at a time. Efficient for small data sets, not efficient for large data sets. Most of...

## Find Largest and Smallest word in a given String

Objective: Given a String, write a program to find largest and smallest word in it. Example: Input String: test Smallest Word: test Largest Word: test —————— Input String: This problem is solved at Algorithms...

## Check if Given Number is power of 2.

Objective: Given a number, write a program to find if number is power of two. Example: N = 5 Output: false. N = 8 Output: true (23) N = 512 Output: true (29) Approach:...

## Rotate the given array in cycles

Objective: Given an array of integers, write a program to rotate the array in cyclic manner by one. Example: Int a [] = {1, 2, 3, 4, 5} Output:  {2, 3, 4, 5, 1}...

## Heap Sort – Java Implementation

What is Heap Sort?? Heap sort is comparison based sorting algorithm. Heap sort is considered as improved selection sort, it divides the input into sorted and unsorted region. The improvement from selection sort is...

## Print First n numbers in Fibonacci Series

Objective: Write a program to print first n numbers in Fibonacci series. Fibonacci number: First two Fibonacci numbers are defined as 0 and 1 and every number after the first two is the sum...

## Find the Area and Perimeter of Rectangle – Java Program

A rectangle is a quadrilateral with four right angles. Say rectangle is given with side’s length A and B Area of Rectangle = A * B Perimeter of rectangle = 2(A+B) Code: Run This Code Output: Area of Rectangle:...