A feedback edge set in a graph refers to a set of edges that, when removed from the graph, eliminates all cycles or feedback loops. In other words, it is a subset of edges that, when deleted, transforms the original graph into a directed acyclic graph (DAG). A good feedback edge set is a feedback edge set that has the minimum possible number of edges. In this tutorial, we will learn to find a Good Feedback Edge Set in a Graph. Problem Statement Write a Java program that identifies and removes feedback edges in a graph to construct a Good ... Read More

In Java programming, there are scenarios where we need to extract individual digits from an integer for further manipulation or analysis. This tutorial will guide you through the process of extracting digits from a given integer using Java. Syntax while (num > 0) { int digit = num % 10; System.out.println(digit); num = num / 10; } The above is the syntax to extract digits from an integer in Java. We keep extracting the last digit by taking the remainder of the number with 10. We divide the number by 10 until it ... Read More

The Zhu-Takaoka algorithm is one of the best algorithms for pattern matching. It is developed using the combination of the Boyer-Moore and KMP string-matching algorithms. The Zhu-Takaoka algorithm utilizes the good character shift and bad character shift techniques to solve the problem. Problem statement − We have given two strings. We need to implement the Zhu-Takaoka algorithm for pattern matching. Sample Examples Input str = "PQRDPQRSSE"; patt = "PQRS"; Output 5 Explanation The ‘PQRS’ pattern exists at position 5. So, it prints 5. Input str = "PQRDPQRSSE"; patt = "PRQS"; Output -1 Explanation ... Read More

The naïve approach to finding the prime numbers in the given range is to check whether each number is prime. Also, we need to make iterations equal to the given number to check whether the number is prime. So, the naïve approach is very time-consuming, and we need to optimize it to make it time efficient. In this tutorial, we will learn wheel factorization and Sieve of Eratosthenes algorithms given by Sieve to find the prime numbers in the given range efficiently. Problem statement − We have given left and right integer values. We need to implement the Wheel factorization ... Read More

In this problem, we will find all palindromic substrings of the given length. There are two ways to solve the problem. The first way is to compare the characters of substring from start to last, and another way is to reverse the substring and compare it with the original substring to check whether the substring is palindrome. Problem statement − We have given a string alpha. We need to find all palindromic substrings of the given string. Sample Examples Input alpha = "abcd" Output 4 Explanation The palindromic substrings are ‘a’, ‘b’, ‘c’, and ‘d’. Input alpha ... Read More

In this problem, we will find two array elements such that the difference between them is maximum. We can make a pair of each element and find the difference between the elements of each pair. After that, we can take a pair whose element has a maximum difference. Another approach is to sort the array and take the largest and smallest element from the array. Problem statement − We have given an array containing the integer values. We need to find two array elements to maximize the difference between them. Sample Examples Input array[] = { 50, 10, 30, ... Read More

Understanding and effectively utilizing Java's functional interfaces is an essential skill for any modern Java developer. Among these interfaces, the ToDoubleFunction interface is a significant tool that offers tremendous utility. This article aims to provide a comprehensive exploration of the ToDoubleFunction interface in Java, enriched with practical examples to enhance your understanding. What is the ToDoubleFunction Interface? Introduced in Java 8, the ToDoubleFunction interface is a part of the java.util.function package. It represents a function that accepts an argument of one type and produces a double-valued result. Its primary use is in lambda expressions and method references where a function ... Read More

Introduction In Java, the manipulation and handling of time is a common requirement in programming tasks. The TimeUnit class, part of java.util.concurrent package, plays a crucial role in this aspect by providing a set of methods for converting time across different units. In this article, we delve into the TimeUnit class, its applications, and practical examples to illustrate its usefulness. Understanding TimeUnit in Java The TimeUnit class in Java provides methods for time conversions and thread-sleep operations with better readability and precision than standard approaches. TimeUnit defines the following time units: DAYS, HOURS, MICROSECONDS, MILLISECONDS, MINUTES, NANOSECONDS, and SECONDS, each ... Read More

Introduction Java concurrency provides several classes and tools that allow developers to create multi-threaded applications. Among these are the ThreadPoolExecutor and Semaphore classes. The former is used to manage a pool of worker threads, while the latter can limit the number of threads accessing a certain resource at a given time. This article delves into throttling the task submission rate using these two Java classes. By understanding how to effectively manage threads and control their execution, you can significantly optimize your Java applications. Understanding ThreadPoolExecutor and Semaphore Before we jump into how to throttle the task submission rate, it's essential ... Read More

Are you embarking on a journey into the realm of multi-threaded programming in Java? Are you finding yourself tangled in the web of classes Java offers for generating random numbers, such as ThreadLocalRandom and SecureRandom? Fear not! This article will break down the differences, similarities, and suitable use-cases for these two classes, ensuring you choose the right tool for your needs. Understanding ThreadLocalRandom in Java Java's ThreadLocalRandom class was introduced in Java 7 to handle the generation of random numbers in a multi-threaded environment more efficiently. The class is part of the java.util.concurrent package and is essentially a stripped-down version ... Read More