Java program to display prime numbers from 1 to 100

Let’s learn prime number program in java and java program to display prime numbers from 1 to 100.

java program to display prime numbers from 1 to 100

Java program to find prime numbers is most common java interview question.

Java program to display prime numbers from 1 to 100

A prime number is one which is divisible by 1 and itself. Here’s the prime number from 1 to 100 program in java,

Also read – java program to check whether number is prime or not

// java code for prime number
public class PrimeNumbersJava
{
   public static void main(String[] args)
   {
      int a = 0;
      int number = 0;
      String strPrimeNumber = "";
      for(a = 1; a <= 100; a++)
      {
         int counter = 0;
         for(number = a; number >= 1; number--)
         {
            if(a % number == 0)
            {
               counter = counter + 1;
            }
         }
         if(counter == 2)
         {
            strPrimeNumber = strPrimeNumber + a + " ";
         }
      }
      System.out.println("Prime numbers from 1 to 100 : ");
      System.out.println(strPrimeNumber);
   }
}

Output:

Prime numbers from 1 to 100 : 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

Similarly we can display from 1 to n. Here’s the java code for prime number,

import java.util.Scanner;

public class PrimeNumber
{
   public static void main(String[] args)
   {
      Scanner sc = new Scanner(System.in);
      int a = 0;
      int number = 0;
      String strPrimeNumber = "";
      System.out.println("Please enter the value of n : ");
      int n = sc.nextInt();
      for(a = 1; a <= n; a++)
      {
         int count = 0;
         for(number = a; number >= 1; number--)
         {
            if(a % number == 0)
            {
               count = count + 1;
            }
         }
         if(count == 2)
         {
            strPrimeNumber = strPrimeNumber + a + " ";
         }
      }
      System.out.println("Prime numbers from 1 to n : ");
      System.out.println(strPrimeNumber);
      sc.close();
   }
}

Output:

Please enter the value of n : 200
Prime numbers from 1 to n :
2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97 101 103 107 109 113 127 131 137 139 149 151 157 163 167 173 179 181 191 193 197 199