In java using command line argument write prime number program?

Answer 1

/* Program to print prime numbers up to given number */

import java.util.*;

public class Prime

{

public static void main(String args[])

{

Scanner sc=new Scanner(System.in);

System.out.println("Enter the number : (it prints prime numbers upto your given number)");

int n=sc.nextInt();

System.out.println("The Prime number upto "+n+" are : ");

while (n>=0)

{

int count=0;

for (int i=1;i<=n ;i++)

{

if (n%i==0)

{

count++;

}

}

if (count==2)

{

System.out.print(n+" ");

}

n--;

}

}

}

Answer 2

/*To find whether a number is prime or not (simplest program)*/

import java.io.*;

class PrimeOrNot

{

public static void main() throws IOException

{

InputStreamReader ir = new InputStreamReader(System.in);

BufferedReader br = new BufferedReader(ir);

System.out.println("Enter the number");

double n = Double.parseDouble(br.readLine());

System.out.println();

int k, l=0;

for (k=1; k<=n; k++)

{

if(n%k==0)

{

l=l+1;

}

}

if(l==2)

{

System.out.println();

System.out.println(n+" is a prime number");

}

else

{

System.out.println();

System.out.println(n+" is NOT a prime number");

}

}

}

Answer 3

import java.util.*;

class Prime

{

public static void main(String s[])

{

int a,c=0;

Scanner sc=new Scanner(System.in);

System.out.println("enter a number");

a=sc.nextInt();

for(int i=1;i<=a;i++)

if(a%i==0)

c++;

if(c==2)

System.out.println("prime number");

else

System.out.println("not a prime number");

}

}

Answer 4

class Prime{

public static void main(String args[]){

int flag=0;

int n=Integer.parseInt(args[0]);

for(int i=1;i<=n;i++){

if(n%i==0)

flag++;

}

if(flag==2)

System.out.println("It is prime");

else

System.out.println("It is not prime");

}

}

Answer 5

int n=<desired number>;

int i=2; // using 2 because every no is divisible by 1

boolean prime=false;

loop : while(i<n){

if(n%i==0){

prime = true;

break loop;

}

i++;

}

System.out.println(prime); // prints true if no is prime, false if it's not

Answer 6

A single input (the number) would look something like...

public static void main(String args) {

try {

// Get an integer

int num = Integer.parseInt(args)

// Must divide by something... start at two

int denom = 2;

// Keep dividing by larger numbers until there's no remainder

// or there's nothing left to try.

// Could probably stop even sooner, but just a sample answer

while(num % denom != 0 && denom < num){

denom++;

}

// If the while loop finished early, it's Optimus!

if(denom < num) {

System.out.println("We have a prime!");

} else {

System.out.println("Not prime... must be Megatron");

}

} catch (ParseException pe) {

System.out.println("Not prime; only integers can be prime. Input an integer number.");

}

}