Project Euler #3
- by Alex
Question:
The prime factors of 13195 are 5, 7, 13 and 29.
What is the largest prime factor of the number 600851475143?
I found this one pretty easy, but running the file took an extremely long time, it's been going on for a while and the highest number I've got to is 716151937.
Here is my code, am I just going to have a wait or is there an error in my code?
//User made class
public class Three
{
public static boolean checkPrime(long p)
{
long i;
boolean prime = false;
for(i = 2;i<p/2;i++)
{
if(p%i==0)
{
prime = true;
break;
}
}
return prime;
}
}
//Note: This is a separate file
public class ThreeMain
{
public static void main(String[] args)
{
long comp = 600851475143L;
boolean prime;
long i;
for(i=2;i<comp/2;i++)
{
if(comp%i==0)
{
prime = Three.checkPrime(i);
if(prime==true)
{
System.out.println(i);
}
}
}
}
}
