Learn how to check whether two strings are rotations of each other in Java using logical string comparison without using complex libraries.
Last updated: 12/23/2025
A detailed explanation of Disarium Numbers in Java with definition, examples, step-by-step logic, and a complete Java program. Ideal for beginners, students, and coding interview preparation.
Last updated: 11/29/2025
Learn how to find the shortest word in a sentence in Java using a simple character-by-character approach without using split() or advanced string methods.
Last updated: 12/19/2025
Learn what an abundant number is in Java with definition, examples, and a clean program to check whether a number is abundant or not.
Last updated: 12/5/2025
Learn how to concatenate two strings in Java without using the + operator. This blog explains the logic with examples, a Java program, and practice challenges.
Last updated: 12/18/2025
A Perfect Square is a number that can be expressed as the square of an integer. This guide explains the concept with examples and provides a simple Java program to check if a number is a perfect square.
Last updated: 12/4/2025
Learn how to check whether a string is null or empty in Java. This blog explains the difference, common mistakes, examples, and a safe Java program with practice challenges.
Last updated: 12/18/2025
Learn how to convert a string to uppercase in Java without using built-in String methods. This blog explains the ASCII-based logic with examples, a Java program, and practice challenges.
Last updated: 12/17/2025
Learn how to reverse a string in Java using a simple and efficient approach. This blog explains the logic step by step with examples, a Java program, and practice challenges.
Last updated: 12/17/2025
Understand how the LOOK Elevator Algorithm optimizes elevator movement by serving only requested floors. Learn its working with examples and a Java program simulating a single elevator.
Last updated: 12/17/2025
Learn how to check for twin prime numbers in Java with clear definition, examples, and a program to find twin primes efficiently.
Last updated: 12/5/2025
Learn what a palindrome number is and how to check it in Java using loops, strings, recursion, and optimized techniques. This guide includes examples, edge cases, and clean explanations.
Last updated: 11/28/2025
Learn what an Odious Number is in Java and number theory. Understand its definition, binary representation rules, examples, and how to check Odious Numbers using Java. Includes example table and 3 practice challenges.
Last updated: 12/1/2025
Learn what an Evil Number is in Java and number theory. Understand its definition, binary representation rules, examples, and how to check Evil Numbers using Java. Includes example table and 3 practice challenges.
Last updated: 12/1/2025
Learn what a Pronic Number is in Java with clear explanations, examples, and a complete Java program. Understand how to identify Pronic Numbers and practice with 3 coding challenges.
Last updated: 11/30/2025
Learn how to check whether two strings are anagrams in Java. This blog explains the concept, examples, and a clean Java program using character frequency logic.
Last updated: 12/18/2025
A Fascinating Number is a number which, when multiplied by 2 and 3 and then concatenated with itself, forms a string that contains all digits from 1 to 9 exactly once.
Last updated: 12/3/2025
Learn how to count consonants in a string using Java. This blog explains the concept with examples, a simple Java program, and practice challenges for beginners.
Last updated: 12/17/2025
Learn how to toggle the case of each character in a string using Java. This program converts uppercase letters to lowercase and lowercase letters to uppercase without using built-in case conversion methods.
Last updated: 12/19/2025
Learn how to find common characters between two strings in Java using simple logic and character comparison without using advanced collections.
Last updated: 12/23/2025
Learn how to calculate the cube root of any number in Java without using the math.cbrt() function. This guide explains an efficient binary search method that works for both integers and decimals.
Last updated: 12/4/2025
Learn how to check whether a string contains all unique characters in Java using simple logic, without using advanced data structures or built-in utilities.
Last updated: 1/2/2026
Learn what a Strong Number is, how it works, and how to write an efficient Java program to check if a number is strong. Includes explanation, examples, algorithm, and clean Java implementation.
Last updated: 11/29/2025
Learn how the SCAN (Elevator) Algorithm can be extended to handle multiple elevators efficiently. This blog explains the concept, working, and includes a Java simulation for multi-elevator scheduling.
Last updated: 12/17/2025
Learn how to count vowels in a string using Java. This blog explains the logic with step-by-step examples, a simple Java program, and practice challenges for beginners.
Last updated: 12/17/2025
Learn how to check whether one string is a subsequence of another string in Java using a simple two-pointer approach without modifying the original strings.
Last updated: 12/23/2025
Learn how to find the first repeating character in a string using Java. This blog explains the logic, examples, and a clean Java program with practice challenges.
Last updated: 12/18/2025
Learn how to check if two numbers are co-prime in Java, with a simple explanation, examples, and a program using the GCD method.
Last updated: 12/5/2025
Learn how to check whether a number is a Perfect Square in Java without using Math.sqrt(). This guide explains the logic, provides examples, and includes an efficient program using iterative checking.
Last updated: 12/4/2025
Learn how to count the frequency of each character in a string using Java. This blog explains the logic, examples, and a clean Java program for beginners and interview preparation.
Last updated: 12/19/2025
Learn everything about Lychrel Numbers in Java with step-by-step explanation, reverse-add process, complete examples, palindrome checks, and why some numbers never form a palindrome. This guide also explores why checking the original number in the loop fails, how HashSets detect loops, and provides a fully working Java program with practice challenges.
Last updated: 12/2/2025
Learn how to calculate the square root of any number in Java without using Math.sqrt(). This guide explains the binary search method, includes examples, and provides a clean Java program.
Last updated: 12/4/2025
Learn what a Spy Number is in Java with clear explanations and examples. This blog covers the definition, logic, step-by-step approach, and a clean Java program to check whether a number is a Spy Number. Includes practice challenges to improve your number theory skills.
Last updated: 12/1/2025
Learn what a Sunny Number is in Java with definition, examples, logic, and a complete Java program. Understand how to check Sunny Numbers and practice with 3 coding challenges for students.
Last updated: 12/1/2025
A beginner-friendly guide to understanding and generating Fibonacci numbers in Java. Learn the logic behind the Fibonacci sequence, explore multiple implementations including loops, recursion, and dynamic programming, and understand when to use each method effectively.
Last updated: 11/27/2025
A clear and detailed guide on Automorphic Numbers in Java, including definition, examples, logic breakdown, and a complete Java program. Ideal for beginners, students, and coding interview preparation.
Last updated: 11/29/2025
Learn how to find duplicate characters in a string using Java. This blog explains the concept, examples, and an efficient Java program using character frequency.
Last updated: 12/18/2025
Learn what a deficient number is in Java with definition, examples, and a simple program to check whether a number is deficient or not.
Last updated: 12/5/2025
Learn what a Buzz Number is in number theory and Java programming. Understand its rules, examples, and how to check Buzz Numbers using Java. Includes sample program, table of examples, and 3 practice challenges.
Last updated: 12/25/2025
Learn how to find the second shortest word in a sentence in Java using a simple character-by-character approach without using split() or advanced string methods.
Last updated: 12/19/2025
Learn how to compare two strings in Java without using the equals() method. This blog explains character-by-character comparison with examples, a Java program, and practice challenges.
Last updated: 12/17/2025
Learn how to print each character of a string in Java using loops. This blog explains the concept with examples, a simple Java program, and practice challenges.
Last updated: 12/17/2025
Learn what a Happy Number is and how to check whether a number is happy or not in Java. This guide explains the concept, algorithm, working process, dry run, and provides multiple Java programs for beginners.
Last updated: 11/29/2025
Learn how to count the frequency of each character in a string using Java. This blog explains the logic, examples, and a clean Java program for beginners and interview preparation.
Last updated: 12/19/2025
Learn how to convert a decimal number to binary in Java with clear explanation, step-by-step examples, and an easy-to-understand program.
Last updated: 12/5/2025
Learn how to perform prime factorization in Java with a clear explanation, examples, and an efficient program that breaks a number into its prime factors.
Last updated: 12/5/2025
A Perfect Square is a number that can be expressed as the square of an integer. This guide explains the concept with examples and provides a simple Java program to check if a number is a perfect square.
Last updated: 12/4/2025
Learn what a palindrome string is and how to check it in Java. This blog explains the concept with examples, a simple Java program, and practice challenges for beginners.
Last updated: 12/17/2025
Learn how to calculate the square root of any number in Java using the Newton–Raphson numerical method. This efficient algorithm provides fast and accurate results without using Math.sqrt().
Last updated: 12/4/2025
Learn what a Sad Number is in Java with clear explanation and logic. This blog covers the definition of a Sad Number, how it differs from a Happy Number, examples, and a complete Java program. Includes practice challenges to strengthen your number theory concepts.
Last updated: 12/1/2025
Learn how real elevators efficiently handle multiple floor requests using the SCAN (Elevator) Algorithm. This blog explains the concept with examples and a Java program simulating a single elevator.
Last updated: 12/17/2025
Learn how to remove all whitespaces from a string in Java using a simple character-based approach without relying on regular expressions or built-in replace methods.
Last updated: 12/19/2025
Learn how to determine if a number is a perfect cube in Java without using the built-in math.cbrt() function. This method uses simple iteration and works for both positive and negative numbers.
Last updated: 12/4/2025
Learn how to reverse each word in a sentence in Java while keeping the word order intact, using a character-based approach without advanced string libraries.
Last updated: 12/19/2025
A Perfect Cube is a number that can be expressed as the cube of an integer. This guide explains the concept with examples and provides a simple Java program to check if a number is a perfect cube.
Last updated: 12/4/2025
Learn how to count digits in a string using Java. This blog explains the logic with examples, a simple Java program, and practice challenges for beginners.
Last updated: 12/17/2025
Learn how to find the first non-repeating character in a string using Java. This blog explains the logic with examples, a clean Java program, and practice challenges.
Last updated: 12/18/2025
Learn how to reverse a number in Java using different methods such as loops, arithmetic operations, and recursion. This beginner-friendly explanation includes logic breakdown, examples, dry run, and multiple Java programs.
Last updated: 11/29/2025
Learn how to replace each space in a string with a given character using Java. This blog explains the logic, examples, and a Java program without using replace() method.
Last updated: 12/19/2025
Learn what a Smith Number is in Java. Understand its definition, rules, examples, and how to check a Smith Number using Java. Includes detailed explanation and 3 practice challenges for students.
Last updated: 11/30/2025
Learn what a Duck Number is in Java programming. Understand its rules, see examples, and learn how to check a Duck Number using Java. Includes 3 detailed practice challenges.
Last updated: 11/30/2025
Learn how to check whether a number is a Buzz Number in Java without using the modulo (%) operator, using simple arithmetic logic and clean programming concepts.
Last updated: 12/25/2025
Learn the most commonly used String library functions in Java with clear explanations, examples, and use cases to write efficient and readable programs.
Last updated: 12/24/2025
A detailed guide on Armstrong Numbers in Java. Learn what an Armstrong number is, how it works, and how to write efficient Java programs to check Armstrong numbers using loops and mathematical logic. Includes clear explanations, examples, and optimized Java code.
Last updated: 11/26/2025
Learn how to check if a number is prime in Java using multiple approaches including loops, optimized methods, and efficient algorithms. This guide covers definitions, characteristics, beginner-friendly programs, and performance-oriented solutions.
Last updated: 11/27/2025
A detailed explanation of Kaprekar Numbers in Java with examples, logic breakdown, and a complete Java implementation. This article also includes beginner-friendly practice challenges to help you strengthen number-system and loop-based problem-solving skills.
Last updated: 11/29/2025
The LCM of two numbers is the smallest number that is perfectly divisible by both. This article explains the concept with examples and provides a simple and efficient Java program.
Last updated: 12/4/2025
Understand how elevators work behind the scenes by simulating real-life lift logic using a simple Java program and step-by-step explanation.
Last updated: 12/17/2025
Learn how to count words in a sentence using Java. This blog explains the logic with examples, a clean Java program, and practice challenges for beginners.
Last updated: 12/17/2025
Learn how to find the longest word in a sentence in Java using a simple character-by-character approach without relying on split() or advanced string methods.
Last updated: 12/19/2025
Learn what a Tech Number is in Java and number theory. Understand the definition, steps, examples, and Java program to check Tech Numbers. Includes sample table and 3 practice challenges.
Last updated: 12/1/2025
The GCD or HCF of two numbers is the largest number that divides both without leaving a remainder. This article explains the concept with examples and provides an efficient Java program using the Euclidean Algorithm.
Last updated: 12/4/2025
Learn how to count spaces in a string using Java. This blog explains the concept with examples, a simple Java program, and practice challenges for beginners.
Last updated: 12/17/2025
Learn how to find common characters between two strings in Java using simple logic, nested loops, and without using advanced data structures.
Last updated: 1/2/2026
Understand what a perfect number is, how it works mathematically, and learn multiple Java programs to check perfect numbers using loops, functions, optimization, and ranges. Includes examples and clean explanations for beginners.
Last updated: 11/28/2025
A Peterson Number is a number in which the sum of the factorials of its digits is equal to the original number.
Last updated: 12/3/2025
Learn everything about Harshad (Niven) Numbers in Java. This blog explains what a Harshad number is, how it works, real examples, properties, and a clean Java program to check whether a number is Harshad. Includes practice challenges to strengthen your understanding.
Last updated: 12/1/2025
Learn how to convert a binary number to decimal in Java with clear explanation, step-by-step examples, and a simple program.
Last updated: 12/12/2025
Learn how to convert a string to lowercase in Java without using built-in String methods. This blog explains the ASCII-based logic with examples, a Java program, and practice challenges.
Last updated: 12/17/2025
A detailed guide on Neon Numbers in Java with definition, examples, logic explanation, and a complete Java program. Ideal for beginners, students, and coding interview preparation.
Last updated: 11/29/2025
Learn how to find the length of a string in Java without using the built-in length() method. This blog explains the logic with examples, a Java program, and practice challenges.
Last updated: 12/17/2025
Learn how to sort characters in a string in Java using a simple comparison-based approach without using built-in sorting utilities.
Last updated: 12/22/2025