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Java beginner needing help with Random Prime Number Generator.

CampbellJCampbellJ Posts: 1Member
Here is my dilemma...

I am in my first programming course, and I am supposed to be developing a random prime number generator. Unfortunately I have hit a snag and need some assistance. Can anyone help me? My source code is below, my issue is when I run my set of numbers (2-20) only 2 is registered as prime and the rest go as not prime. Any suggestions?

import java.util.*;
public class PNG
public static void main(String[] args)
int num1, num2, count, i = 2, prChk = 0 , m = 0;
Scanner keyIn = new Scanner (;

System.out.print("Enter First number : ");
num1 = keyIn.nextInt();

System.out.print("Enter Second number : ");
num2 = keyIn.nextInt();

count = num1;

while(count <= num2)
while(i < count)
prChk = count % i;
if(prChk == 0)
m = 0;
else if(prChk == 1)
m = 1;
if (m == 0)
System.out.println(count + ": prime");
else if(m ==1)
System.out.println(count + ": not prime");

Thanks again!

James Campbell
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