program to display prime numbers from 1 to 100 code example

Example 1: prime numbers from 1 to 100

// find all numbers prime java
public class IsNumberIsSimple {
       
        public static void main (String args[]) {
        
            for ( int i=0; i < 100; i++) {
              isNumberIsSimple(i);
            }     
        }   
        
        public void isNumberIsSimple(num){
        	for ( int i=2; i < num; i++) {
                  if ( num%i == 0) {
                          return;
                  }      
          	}
          	System.out.println("Very well! It's simple! " + num);   
        }
}

//1, 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

Example 2: Java program to display prime numbers from 1 to 100

public class PrimeNumbersFrom1To100
{
   public static void main(String[] args)
   {
      int maxNumber = 100;
      boolean prime = true;
      String primeNumbers = "";
      for(int a = 1; a <= maxNumber; a++)
      {
         prime = checkPrime(a);
         if(prime)
         {
            primeNumbers = primeNumbers + a + " ";
         }
      }
      System.out.println("Display prime numbers from 1 to " + maxNumber + ": ");
      System.out.println(primeNumbers);
   }
   public static boolean checkPrime(int number)
   {
      int remainder;
      for(int a = 2; a <= number / 2; a++)
      {
         remainder = number % a;
         // if remainder is equal to 0 then number is not prime
         if(remainder == 0)
         {
            return false;
         }
      }
      return true;
   }
}