Java program print prime numbers from 1 to 100 or 1 to n

A number which is divided by one and itself is called prime . I will suggest to you first read this article how to check given number is prime or not in java . Now i am thinking you know about what is prime number and how  to check prime number in java. In this post we will see how to print prime number 1 to 100 in java .

Java program to print prime numbers between 1 to 100

In this program we will write java program to display prime number from 1 to  100 . For this we use this  algorithm

1.  Iterate loop 1 to 100

2. for each iterate check number prime or not

3. print number if it is prime .

public class PrimeNumberToRange {

	public static void main(String[] args) {
		System.out.println("prime number between 1 to 100 :");
		for (int i = 1; i <= 100; i++) {
			if (isPrimeNumber(i)) {
				System.out.print(i + " ");
			}
		}
	}

	private static boolean isPrimeNumber(int num) {
		if (num <= 1) {
			return false;
		}
		boolean flag = true;
		for (int j = 2; j <= Math.sqrt(num); j++) {
			if (num % j == 0) {
				flag = false;
				break;
			}
		}
		return flag;
	}

}

Output :

prime number between 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

We have printed prime numbers from 1 to 100 in java using for loop. We can use while loop alsoin same algorithm .

Java program to print prime numbers between 1 to n

print prime numbers from 1 to n in java . we will print list of prime numbers from 1 to n using for loop. n take as input from user.

import java.util.Scanner;

public class PrimeNumberToRange {

	public static void main(String[] args) {
		Scanner scan= new Scanner(System.in);
		System.out.println("Enter value of n:");
		int n  =scan.nextInt();
		System.out.println("prime number between 1 to "+ n +" : ");		
		for (int i = 1; i <= n; i++) {
			if (isPrimeNumber(i)) {
				System.out.print(i + " ");
			}
		}
	}

	private static boolean isPrimeNumber(int num) {
		if (num <= 1) {
			return false;
		}
		boolean flag = true;
		for (int j = 2; j <= Math.sqrt(num); j++) {
			if (num % j == 0) {
				flag = false;
				break;
			}
		}
		return flag;
	}

}

Output:

Enter value of n:
10
prime number between 1 to 10 : 
2 3 5 7

In this program we have print prime number 1 to 10 . With the help of this example we can print prime numbers between 1 to 50 or print prime numbers from 1 to 1000 or print prime numbers 1 to 200 or print prime numbers from 1 to 20 etc.

Java Program to Display Prime Numbers Between Two Intervals

Now we will write java program to print prime numbers in a given range.

import java.util.Scanner;

public class PrimeNumberInterval {
	
	public static void main(String[] args) {
		Scanner scan= new Scanner(System.in);
		System.out.println("Enter value of low:");
		int low  =scan.nextInt();
		System.out.println("Enter value of high:");
		int high  =scan.nextInt();
		scan.close();
	  System.out.println("prime number between "+low+" to "+ high +" : ");		
	for (int i = low; i <= high; i++) {
			if (isPrimeNumber(i)) {
				System.out.print(i + " ");
			}
		}
	}

	private static boolean isPrimeNumber(int num) {
		if (num <= 1) {
			return false;
		}
		boolean flag = true;
		for (int j = 2; j <= Math.sqrt(num); j++) {
			if (num % j == 0) {
				flag = false;
				break;
			}
		}
		return flag;
	}

}

Output :

Enter value of low:
5
Enter value of high:
10
prime number between 5 to 10 : 
5 7

java program to print prime numbers in a given range using for loop . you can write java program to print prime numbers in a given range using while loop using same logic. You can see top java programming interview questions . In this article we have learned print prime  number for  1 to 100 and 1 to n or given range.