Factor listing issues

**skaterboy987** · 10-28-2011, 06:08 AM

OUTDATED, PLEASE DO NOT RESPOND
new post: Greatest Common Factors (Version 2) Storing and Comparing Factors
So my problem is... When my two numbers are 10 and 15,it outputs 0 and it lists out all the factors of 10 then errors... Here's the output:
0
1
2
5
10
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 5
at Greatest_Common_Factor.main(Greatest_Common_Factor .java:30)
(Factors of 15 supposed to be here)

Java Code:


public class Greatest_Common_Factor {
	public static void main (String args[]){    
	int number = 10;
	int number2 = 15;
	int factor1Length = 0;
	int itterations = 0;
	int itterations2 = 0;
	int[] factors1; 
	int[] factors2;
	factors1 = new int[1 + getFactor1Length(number)]; //Gets all factors of number
	factors2 = new int[1 + getFactor2Length(number2)]; // Gets all factors of number 2

	for(int x=1; x<=(number); x++){ //puts all factors of num1 into factors1 array
		if(number % x == 0){
			itterations++;
		factors1[itterations] = x;
		}//end if
	}//end for
	
	for(int y=1; y<=(number2); y++){
		if(number2 % y == 0){
			itterations2++;
			factors2[itterations2] = y;
		}//end if
	}//end for
	
	//Print all factors of everything
	for(int a=0; a<=factors1.length; a++){
		System.out.println(factors1[a]);
	}
	for(int b=0; b<=factors2.length; b++){
		System.out.println(factors1[b]);
	}
	
	
	
}//end main
	
	
	
	
	
	
//**********************Get Factor 2 Length****************************	
private static int getFactor2Length(int number2) {
	int factor2Length = 0;
	for(int i=1; i<=(number2); i++){
	if(number2 % i == 0){
		factor2Length++;
	}//end if
	}//end for
	return factor2Length;
}//end method







//**********************Get Factor Length****************************
	private static int getFactor1Length(int number) {
		int factor1Length = 0;
		for(int i=1; i<=(number); i++){
			if(number % i == 0){
			factor1Length++;
			}//end if
		}//end for
		return factor1Length;
	}//end method

		
		

}//end class

**Junky** · 10-28-2011, 06:58 AM

Why do you have 2 methods (getFactorLength) that do the same thing?

**Junky** · 10-28-2011, 07:14 AM

More duplication.

The 2 loops calculating the factors do the same thing.
The 2 loops printing out the factors do the same thing.

Other issues

Why do you make the arrays 1 larger than the number of factors.
The two print loop prints out the factors from the same array. However if you delete the duplication this will be fixed.
Check the end condition of the print loop. This is why you get the AIOOBE.

**skaterboy987** · 10-28-2011, 09:00 PM

When I take away the +1 I get this error
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 4
at Greatest_Common_Factor.main(Greatest_Common_Factor .java:16)

**skaterboy987** · 10-28-2011, 09:02 PM

Ignore the post above this one, it's stupid, I gotta fix everything first

**skaterboy987** · 10-28-2011, 09:14 PM

The 2 loops calculating the factors do the same thing. They do the same process but with different variables.
The 2 loops printing out the factors do the same thing. They do the same process but the arrays are different

Other issues

Why do you make the arrays 1 larger than the number of factors. So I don't get this error:
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 4
at Greatest_Common_Factor.main(Greatest_Common_Factor .java:16)
Which I get when I delete the + from these

Java Code:

 factors1 = new int[1 + [getFactor1Length(number)]; //Gets all factors of number
 factors2 = new int[1 + [getFactor2Length(number2)]; // Gets all factors of number 2

The two print loop prints out the factors from the same array. However if you delete the duplication this will be fixed. You're right, fixed it.
Check the end condition of the print loop. This is why you get the AIOOBE. Aha! That's it except it will only print out the numbers if I add the 1 + to the getfactor1length

NEW CODE

Java Code:

public class Greatest_Common_Factor {
    public static void main (String args[]){    
    int number = 10;
    int number2 = 15;
    int factor1Length = 0;
    int itterations = 0;
    int itterations2 = 0;
    int[] factors1; 
    int[] factors2;
    factors1 = new int[1+getFactor1Length(number)]; //Gets all factors of number
    factors2 = new int[1+getFactor2Length(number2)]; // Gets all factors of number 2
 
    for(int x=1; x<=(number); x++){ //puts all factors of num1 into factors1 array
        if(number % x == 0){
            itterations++;
        factors1[itterations] = x;
        }//end if
    }//end for
     
    for(int y=1; y<=(number2); y++){
        if(number2 % y == 0){
            itterations2++;
            factors2[itterations2] = y;
        }//end if
    }//end for
     
    //Print all factors of everything
    for(int a=0; a<=factors1.length; a++){
        System.out.println("Factor 1 factor " + factors1[a]);
    }
    for(int b=0; b<=factors2.length; b++){
        System.out.println("Factor 2 factor " + factors2[b]);
    }
     
     
     
}//end main
     
     
     
     
     
     
//**********************Get Factor 2 Length**************************** 
private static int getFactor2Length(int number2) {
    int factor2Length = 0;
    for(int i=1; i<=(number2); i++){
    if(number2 % i == 0){
        factor2Length++;
    }//end if
    }//end for
    return factor2Length;
}//end method
 
 
 
 
 
 
 
//**********************Get Factor Length****************************
    private static int getFactor1Length(int number) {
        int factor1Length = 0;
        for(int i=1; i<=(number); i++){
            if(number % i == 0){
            factor1Length++;
            }//end if
        }//end for
        return factor1Length;
    }//end method
 
         
         
 
}//end class

ERRORS / RESULT:

Factor 1 factor 0
Factor 1 factor 1
Factor 1 factor 2
Factor 1 factor 5
Factor 1 factor 10
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 5
at Greatest_Common_Factor.main(Greatest_Common_Factor .java:29)

**skaterboy987** · 10-28-2011, 10:20 PM

WORKING CODE

Java Code:


public class Greatest_Common_Factor {
	public static void main (String args[]){    
	int number = 10;
	int number2 = 15;
	int factor1Length = 0;
	int itterations = 0;
	int itterations2 = 0;
	int[] factors1; 
	int[] factors2;
	factors1 = new int[getFactor1Length(number)]; //Gets all factors of number
	factors2 = new int[getFactor2Length(number2)]; // Gets all factors of number 2

	for(int x=1; x<=(number); x++){ //puts all factors of num1 into factors1 array
		if(number % x == 0){
			itterations++;
		factors1[itterations-1] = x;
		}//end if
	}//end for
	
	for(int y=1; y<=(number2); y++){
		if(number2 % y == 0){
			itterations2++;
			factors2[itterations2-1] = y;
		}//end if
	}//end for
	
	//Print all factors of everything
	for(int a=0; a<=factors1.length-1; a++){
		System.out.println("Factor 1 factor " + factors1[a]);
	}
	for(int b=0; b<=factors2.length-1; b++){
		System.out.println("Factor 2 factor " + factors2[b]);
	}
	
	
	
}//end main
	
	
	
	
	
	
	
private static int getFactor2Length(int number2) {
	int factor2Length = 0;
	for(int i=1; i<=(number2); i++){
	if(number2 % i == 0){
		factor2Length++;
	}//end if
	}//end for
	return factor2Length;
}//end method







//**********************Get Factor Length****************************
	private static int getFactor1Length(int number) {
		int factor1Length = 0;
		for(int i=1; i<=(number); i++){
			if(number % i == 0){
			factor1Length++;
			}//end if
		}//end for
		return factor1Length;
	}//end method

		
		

}//end class

notice the many "-1"
:D

**JosAH** · 10-28-2011, 10:25 PM

Originally Posted by skaterboy987

notice the many "-1"
:D

That is easily fixed: change this:

Java Code:

for(int a=0; a<=factors1.length-1; a++){
         System.out.println("Factor 1 factor " + factors1[a]);     
}

to this:

Java Code:

for(int a=0; a< factors1.length; a++){
         System.out.println("Factor 1 factor " + factors1[a]);     
}

kind regards,

Jos

**skaterboy987** · 10-28-2011, 10:46 PM

Ohhhhhhhhhh! Thats why. Thanks Jos.
Sorry but I have 1 final question. I know there's gotta be some mistake but this is what I'm intending part of the code to do to compare the factors. So lets pretend were comparing 7 to 7 trying to find the the common factors of only 1 and 7. This is what I intend for the program to do.

is 1 = 1
is 1 = 2
is 1 = 3
is 1 = 4
is 1 = 5
is 1 = 6
is 1 = 7
is 2 = 1
is 2 = 2
etc...

Here's the code to compare the numbers

Java Code:

	//Find Common Factors....
	for(int zz=0; zz<(factors1.length); zz++){ 
		for(int z=0; zz<(factors2.length); z++){
		if(factors1[zz] == factors2[z]){
			System.out.println(factors1[z]);
		}//end if	
		}//end for
	}//end for

It only prints 1 then it prints:

Java Code:

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 4
	at Greatest_Common_Factor.main(Greatest_Common_Factor.java:39)

Which is line:

Java Code:

		if(factors1[zz] == factors2[z]){

It only prints 1
For the error I don't understand whats going on :(
Any help is appreciated!

The full code

Java Code:

public class Greatest_Common_Factor {
	public static void main (String args[]){    
	int number = 10;
	int number2 = 15;
	int factor1Length = 0;
	int itterations = 0;
	int itterations2 = 0;
	int[] factors1; 
	int[] factors2;
	factors1 = new int[getFactor1Length(number)]; //Gets all factors of number
	factors2 = new int[getFactor2Length(number2)]; // Gets all factors of number 2

	for(int x=1; x<=(number); x++){ //puts all factors of num1 into factors1 array
		if(number % x == 0){
			itterations++;
		factors1[itterations-1] = x;
		}//end if
	}//end for
	
	for(int y=1; y<=(number2); y++){
		if(number2 % y == 0){
			itterations2++;
			factors2[itterations2-1] = y;
		}//end if
	}//end for
	
	//Print all factors of everything
	for(int a=0; a<=factors1.length-1; a++){
		System.out.println("Factor 1 factor " + factors1[a]);
	}//end for
	for(int b=0; b<=factors2.length-1; b++){
		System.out.println("Factor 2 factor " + factors2[b]);
	}//end for
	
	//Find Common Factors....
	for(int zz=0; zz<(factors1.length); zz++){ 
		for(int z=0; zz<(factors2.length); z++){
		if(factors1[zz] == factors2[z]){
			System.out.println(factors1[z]);
		}//end if	
		}//end for
	}//end for	
}//end main
	
	
	
	
	
	
	
private static int getFactor2Length(int number2) {
	int factor2Length = 0;
	for(int i=1; i<=(number2); i++){
	if(number2 % i == 0){
		factor2Length++;
	}//end if
	}//end for
	return factor2Length;
}//end method







//**********************Get Factor Length****************************
	private static int getFactor1Length(int number) {
		int factor1Length = 0;
		for(int i=1; i<=(number); i++){
			if(number % i == 0){
			factor1Length++;
			}//end if
		}//end for
		return factor1Length;
	}//end method

		
		

}//end class