Java Interview Programs

Interview Practice Index

This page is your one-stop index for Java interview programs. Pick a category below and open any problem directly.

Number Basics

20 programs
Even Number
Odd Number
Natural Number
Composite Number
Prime Number
Perfect Square
Perfect Number
Abundant Number
Strong Number
Armstrong Number
Automorphic Number
Palindrome Number
Happy Number
Harshad Number
Disarium Number
Magic Number
Smith Number
Evil Number
Pronic Number
Triangular Number

Math and Operations

14 programs
Sum of Digits
Condense a Number
Swap Two Numbers
GCD
LCM
Prime Factor
Factorial of a Number
Fibonacci Series
Leap Year
Power of 2
Power of 3
Cube Number
Number Combination
Multiplication Table

Array Programs

6 programs
Sum of Array
Maximum Value of an Array
Minimum Value of an Array
Average of N Numbers
Biggest of Three Numbers
Common Divisors

Matrix and Conversion

10 programs
Matrix Addition
Matrix Subtraction
Matrix Multiplication
Matrix Division
Matrix Transpose
Decimal to Binary
Binary to Decimal
Decimal to Octal
Pascal's Triangle
Amicable Number
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Tip: Practice category by category. Start with basic number checks, then move to arrays, conversions, and matrix programs.

About the author

Mari Selvan M P
Mari Selvan M P 🔗

Developer, cloud engineer, and technical writer

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Java Java Program to Check Abundant Number