(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Write a program that takes a command line argument N and a sequence of N positive integers and prints the numbers that are prime only, followed by their sum.

2. Relevant equations

for loop

3. The attempt at a solution

This has been a vexing program to think of. We were asked to write a program that takes an integer N and outputs true if N is prime and false if N is not prime. The code is as follows:

Although we haven't actually covered the break command, but I didn't know how to code it without it.Code (Text):public class Primes

{

public static void main(String[] args)

{

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

int i;

boolean ifPrime;

for (i = 2; i < numb; i++)

{

int n = numb % i;

if (n == 0)

{

ifPrime = false;

System.out.println(numb + " is not a prime number, hence " + ifPrime);

break;

}

}

if (i == numb)

{

ifPrime = true;

System.out.println(numb + " is a prime number, hence " + ifPrime);

}

}

}

Now, the question above is a little confusing to me, particularly the wording. Does it want to take a command-line value N then N numbers afterward or is it something else?

The way I thought of it is to first write a method of type boolean that studies the integer(s) and then returns true or false if prime or not. We enter a loop in the main method that loops over argswhere i is an initialization variable (int), then use if to compare the returned boolean value if. But here's where I hit the wall. What's next? How do you continue from here?

This is my last question, I hope.

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# Homework Help: Sum of prime numbers taken from the command-line

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