Write a Java program to check prime number. Given an input integer, We have to write an efficient code to check whether a number is prime or not.
Before writing a program, let’s quickly understand what is a prime number.
A prime number is a number that is greater than 1 and it has no positive divisors other than 1 and itself.
For example – 3, 13, 7 is a prime number, as it’s divisible by 1 and itself. Similarly, 29, 19 etc. are also prime numbers.
6 is not a prime number as it’s divisible by 1, 2, 3 and 6.
2 is the only even prime number.
How to check whether a number is prime or not in Java
Write a java program to print Fibonacci series up to N number, where N is the input integer.
Write a program to print 1 to 100 numbers without using loop. Using loop, (for and while loop) we can easily solve this problem. Think for a moment how do you solve this problem without using a loop. We can solve this problem using recursion.
Find Pair of Elements in an Array whose Sum is Equal to given number. Given an array of n integers and a number x, We have to write a code to find a pair of elements(a,b) in an array whose sum is equal to a given number x.