In this program, we will print prime numbers from 1 to 100 in java.

A prime number is a number which has only two divisors 1 and itself. To check if the number is prime or not, we need to see if it has any other factors other than 1 or itself. If it has, then number is not prime else number is prime.

## Algorithm

- Iterate from 1 to 100.
- In each iteration, check is number is prime or not.
- If number is not divisible from 1 to sqrt(n) then number is not prime.
- If number is prime, print it.

### Here is java program to print prime numbers from 1 to 100.

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package org.arpit.java2blog; public class PrintPrimeNumberMain { public static void main(String[] args) { System.out.println("Prime numbers between 1 to 100 are:"); for (int i = 1; i < 100; i++) { if(isPrimeNumber(i)) { System.out.print(" "+i); } } } public static boolean isPrimeNumber(int number) { if (number <= 1) { return false; } for (int i = 2; i <= Math.sqrt(number); i++) { if (number % i == 0) { return false; } } return true; } } |

When you will run above program, you will get below output:

2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97

That’s all about print prime numbers from 1 to 100 in java.