I have gone from 96 lines to 17 lines taking hits at this one. This is what I am left with after all of that effort:

public class IntegerFactoriseFive {

    public static void main(String[] args)
    {
        long n = 600851475143L;
        for (long i = 2; i <= n; i++)
        {
            if (n % i==0)
            {
                System.out.println(i);
                n = n / i;
                i = 2;
            }
        }
    }
}

Is there any way to make it faster?

I'm not suggesting that it isn't quick enough already, but for the sake of it and for improving the way I tackle problems in the future. My other solutions were taking forever. I was using recursion, and I even only iterated up to the square root of the numbers I was checking (from early school maths I know to only check up to the square root, it is a lot quicker), but it was still to slow. In the end, iterating by one and dividing this huge number was the wrong way to go about it, so instead, I figured that dividing the number as much as possible was the only way I could do it in any good time.

Please offer suggestions. As you can see by the class name, it is my fifth official solution for it that is the quickest of the ones I came up with.

Project Euler problem 3 asks for the largest prime factor of 600851475143.

I have gone from 96 lines to 17 lines taking hits at this one. This is what I am left with after all of that effort:

public class IntegerFactoriseFive {

    public static void main(String[] args)
    {
        long n = 600851475143L;
        for (long i = 2; i <= n; i++)
        {
            if (n % i==0)
            {
                System.out.println(i);
                n = n / i;
                i = 2;
            }
        }
    }
}

Is there any way to make it faster?

I'm not suggesting that it isn't quick enough already, but for the sake of it and for improving the way I tackle problems in the future. My other solutions were taking forever. I was using recursion, and I even only iterated up to the square root of the numbers I was checking (from early school maths I know to only check up to the square root, it is a lot quicker), but it was still to slow. In the end, iterating by one and dividing this huge number was the wrong way to go about it, so instead, I figured that dividing the number as much as possible was the only way I could do it in any good time.

Please offer suggestions. As you can see by the class name, it is my fifth official solution for it that is the quickest of the ones I came up with.

I have been told that this is a more appropriate place to ask this question. THe link to this question is Here

Here is the question:

I have gone from 96 lines to 17 lines taking hits at this one, this is what I am left with after all of that effort:

public class IntegerFactoriseFive {

    public static void main(String[] args)
    {
        long n = 600851475143L;
        for (long i = 2; i <= n; i++)
        {
            if (n % i==0)
            {
                System.out.println(i);
                n = n / i;
                i = 2;
            }
        }
    }
    
}

Is there any way to make it faster? I'm not suggesting that it isn't quick enough already, but for the sake of it and for improving the way I tackle problems in the future. My other solutions were taking forever, I was using recursion, I even only iterated up to the square root of the numbers I was checking (from early school maths I know to only check up to the square root, it is a lot quicker), but it was still to slow, in the end iterating by one and dividing this huge number was the wrong way to go about it, so instead I figured that dividing the number as much as possible was the only way I could do it in any good time. Suggestions please, as you can see by the class name it is my fifth official solution for it that is the quickest of the ones I came up with.

I have gone from 96 lines to 17 lines taking hits at this one. This is what I am left with after all of that effort:

public class IntegerFactoriseFive {

    public static void main(String[] args)
    {
        long n = 600851475143L;
        for (long i = 2; i <= n; i++)
        {
            if (n % i==0)
            {
                System.out.println(i);
                n = n / i;
                i = 2;
            }
        }
    }
}

Is there any way to make it faster? 

I'm not suggesting that it isn't quick enough already, but for the sake of it and for improving the way I tackle problems in the future. My other solutions were taking forever. I was using recursion, and I even only iterated up to the square root of the numbers I was checking (from early school maths I know to only check up to the square root, it is a lot quicker), but it was still to slow. In the end, iterating by one and dividing this huge number was the wrong way to go about it, so instead, I figured that dividing the number as much as possible was the only way I could do it in any good time.

Please offer suggestions. As you can see by the class name, it is my fifth official solution for it that is the quickest of the ones I came up with.