Why is this code never reached?

[EscSequenceAlpha]

specs: I'm creating a learning tool for kids that asks a question, what is x times y? where x and y are random integers.

if they score 75% correct then they move up a level otherwise not.

the problem I am having is that the if statement in checkComplete never works (possibly means correct and incorrect never reach 10)

I have tried a few fixes.

1) I realised that when I called the method again after a correct answer it will reassign correct and incorrect as 0, I did put a while(true) loop to block of the code from those declarations but this didnt work (I have taken the while loop out of the code because it messes up the indentation for you guys)

2) does if( checkComplete(correct, incorrect) == true) execute the method or just check the return value? I dont actually know... this is why I tried adding checkComplete(correct, incorrect) above it incase it doesnt execute in the if statement

can you please explain whether a method does execute when put in a conditional statement?

anyway, that didnt work either

heres me code

package chapter_vi;

import java.util.Random;
import java.util.Scanner;

public class ComputerAssistedInstructionMonitoringStudentPerformance_6_37 
{
	public static boolean checkComplete(int correct, int incorrect)
	{
		boolean complete = true;
		
		if( correct + incorrect == 10 )
		{
			System.out.println("You have scored " + correct + " correct, and " + incorrect +
					" incorrect.");
			
			if (correct >= (10/100) * 75)
			{
				System.out.println("Congratulations, you are ready to go to the next level!");
			}
			else
			{
				System.out.println("Please ask your teacher for extra help");
			}
		}

		return complete;
	}
	public static void question()
	{
		Scanner input = new Scanner(System.in);
		Random randomNumbers = new Random();
		
		int random1 = randomNumbers.nextInt(11);
		int random2 = randomNumbers.nextInt(11);
		int answer;
		int result = (random1 * random2);
		int correct = 0;
		int incorrect = 0;
		
		System.out.println("Lets play multiplication");
		System.out.println("What is " + random1 + " times " + random2 + "?");
		answer = input.nextInt();
		
		while( answer != result)
		{
			switch(1 + randomNumbers.nextInt(4))
			{
				case 1:
					System.out.println("No. Please try again.");
					break;
				case 2:
					System.out.println("Wrong. Try once more.");
					break;
				case 3:
					System.out.println("Don't give up!");
					break;
				case 4:
					System.out.println("No. Keep trying.");
			}
			incorrect++;
			if( checkComplete(correct, incorrect) == true)
				{
					question();
				}
			
			System.out.println("What is " + random1 + " x " + random2 + "?");
			answer = input.nextInt();
		}

		switch(1 + randomNumbers.nextInt(4))
		{
			case 1:
				System.out.println("Very good!");
				break;
			case 2:
				System.out.println("Excellent!");
				break;
			case 3:
				System.out.println("Nice work");
				break;
			case 4:
				System.out.println("Keep up the good work");
		}
		correct++;

		if( checkComplete(correct, incorrect) == true)
		{
			question();
		}
		
		System.out.println();
		
	}
	
	public static void main(String[] args)
	{
		question();
	}
}

what do you guys think?

[Wnt2bsleepin]

I did notice that CheckComplete never returns false if it should.

[brynpttrsn]

Yes methods do execute no matter where they are called in the code. And as Wnt pointed out you should have complete be set to false somewhere in that method.

[EscSequenceAlpha]

Yes methods do execute no matter where they are called in the code. And as Wnt pointed out you should have complete be set to false somewhere in that method.

Really? ok I'll try that... but I thought boolean variables once declared would be given the value of false like strings are null, I thought I read taht somewhere or am I confusing things again.

[brynpttrsn]

public static boolean checkComplete(int correct, int incorrect)
    {
        boolean complete = true;
         
        if( correct + incorrect == 10 )
        {
            System.out.println("You have scored " + correct + " correct, and " + incorrect +
                    " incorrect.");
             
            if (correct >= (10/100) * 75)
            {
                System.out.println("Congratulations, you are ready to go to the next level!");
            }
            else
            {
                System.out.println("Please ask your teacher for extra help");
            }
        }
 
        return complete;
    }

In this method you set complete to true. Its not set to false anywhere, so the only possible outcome of this method is returning true.

[EscSequenceAlpha]

Really? ok I'll try that... but I thought boolean variables once declared would be given the value of false like strings are null, I thought I read taht somewhere or am I confusing things again.

Sorry! I forgot what my code was... yes I should move the boolean variable after the if statement, so its false unless 10 answers.

I did this and now it works as it should, thank you guys. and I learned methods do execute even as an argument in a conditional so I took the call out before it

thanks

[EscSequenceAlpha]

also a side question... was it appropriate to use a while in the question method to prevent reinitialisation when method recalled

or would it be more natural to have those variables belong as static class variables and then I wouldnt need a while(true) loop right?

[JosAH]

This isn't related to your problem but you'd better make your number of questions a multiple of four otherwise it's impossible to have a score of exactly 75% ...

kind regards,

Jos

[EscSequenceAlpha]

I saw that too, but the task actually stated 10 questions with 75% - odd I agree.

[EscSequenceAlpha]

Ok almost done, just run into one problem

additions
+ added a difficulty feature, the initial difficulty is set, and if they score above 75% the difficulty increases

problem
the difficulty never seems to increase. after scoring > 75%

[CODE]
package chapter_vi;

import java.util.Random;
import java.util.Scanner;

public class ComputerAssistedInstructionDifficultyLevels_6_38
{
static Scanner input = new Scanner(System.in);

static int difficulty;

public static boolean checkComplete(int correct, int incorrect)
{
boolean complete = false;

if( correct + incorrect == 10 )
{
System.out.println("You have scored " + correct + " correct, and " + incorrect +
" incorrect.");

complete = true;

if (correct >= (10/100) * 75)
{
System.out.println("Congratulations, you are ready to go to the next level!");
difficulty++;
}
else
{
System.out.println("Please ask your teacher for extra help");
}
}

return complete;
}
public static void question(int difficulty)
{
Random randomNumbers = new Random();

int answer;
int random1 = 0;
int random2 = 0;
int result;
int correct = 0;
int incorrect = 0;

while(true)
{

if( difficulty == 1)
{
random1 = randomNumbers.nextInt(11);
random2 = randomNumbers.nextInt(11);
}
else if( difficulty == 2)
{
random1 = randomNumbers.nextInt(101);
random2 = randomNumbers.nextInt(101);
}
else // difficulty 3 (>= 3)
{
random1 = randomNumbers.nextInt(1001);
random2 = randomNumbers.nextInt(1001);
}

result = (random1 * random2);

System.out.println("Lets play multiplication");
System.out.println("What is " + random1 + " times " + random2 + "?");
answer = input.nextInt();

while( answer != result )
{

switch(1 + randomNumbers.nextInt(4))
{
case 1:
System.out.println("No. Please try again.");
break;
case 2:
System.out.println("Wrong. Try once more.");
break;
case 3:
System.out.println("Don't give up!");
break;
case 4:
System.out.println("No. Keep trying.");
}

incorrect++;

if( checkComplete(correct, incorrect) == true)
{
question(difficulty);
}

System.out.println("What is " + random1 + " times " + random2 + "?");
answer = input.nextInt();
}

switch(1 + randomNumbers.nextInt(4))
{
case 1:
System.out.println("Very good!");
break;
case 2:
System.out.println("Excellent!");
break;
case 3:
System.out.println("Nice work");
break;
case 4:
System.out.println("Keep up the good work");
}
correct++;

if( checkComplete(correct, incorrect) == true)
{
question(difficulty);
}

System.out.println();
}
}

public static void main(String[] args)
{
System.out.println("What level of difficulty would you like? (1, 2, 3)");
difficulty = input.nextInt();
question(difficulty);
}
}

[\CODE]

can you spot the problem? I cant

regards,
ESA

[EscSequenceAlpha]

package chapter_vi;

import java.util.Random;
import java.util.Scanner;

public class ComputerAssistedInstructionDifficultyLevels_6_38 
{
	static Scanner input = new Scanner(System.in);
	
	static int difficulty;
	
	public static boolean checkComplete(int correct, int incorrect)
	{
		boolean complete = false;
		
		if( correct + incorrect == 10 )
		{
			System.out.println("You have scored " + correct + " correct, and " + incorrect +
					" incorrect.");
			
			complete = true;
			
			if (correct >= (10/100) * 75)
			{
				System.out.println("Congratulations, you are ready to go to the next level!");
				difficulty++;
			}
			else
			{
				System.out.println("Please ask your teacher for extra help");
			}
		}

		return complete;
	}
	public static void question(int difficulty)
	{
		Random randomNumbers = new Random();
		
		int answer;
		int random1 = 0;
		int random2 = 0;
		int result;
		int correct = 0;
		int incorrect = 0;
		
		while(true)
		{
		
		if( difficulty == 1)
		{
			random1 = randomNumbers.nextInt(11);
			random2 = randomNumbers.nextInt(11);
		}
		else if( difficulty == 2)
		{
			random1 = randomNumbers.nextInt(101);
			random2 = randomNumbers.nextInt(101);
		}
		else // difficulty 3 (>= 3)
		{
			random1 = randomNumbers.nextInt(1001);
			random2 = randomNumbers.nextInt(1001);
		}
		
		result = (random1 * random2);
		
			System.out.println("Lets play multiplication");
			System.out.println("What is " + random1 + " times " + random2 + "?");
			answer = input.nextInt();
		
			while( answer != result )
			{
				
				switch(1 + randomNumbers.nextInt(4))
				{
					case 1:
						System.out.println("No. Please try again.");
						break;
					case 2:
						System.out.println("Wrong. Try once more.");
						break;
					case 3:
						System.out.println("Don't give up!");
						break;
					case 4:
						System.out.println("No. Keep trying.");
				}
			
			incorrect++;
			
			if( checkComplete(correct, incorrect) == true)
				{
					question(difficulty);
				}
			
			System.out.println("What is " + random1 + " times " + random2 + "?");
			answer = input.nextInt();
			}
			
			switch(1 + randomNumbers.nextInt(4))
			{
				case 1:
					System.out.println("Very good!");
					break;
				case 2:
					System.out.println("Excellent!");
					break;
				case 3:
					System.out.println("Nice work");
					break;
				case 4:
					System.out.println("Keep up the good work");
			}
			correct++;

			if( checkComplete(correct, incorrect) == true)
			{
				question(difficulty);
			}
		
			System.out.println();
			}
	}
	
	public static void main(String[] args)
	{
		System.out.println("What level of difficulty would you like? (1, 2, 3)");
		difficulty = input.nextInt();
		question(difficulty);
	}
}

SORRY I did quick reply because reply to thread didnt work for minute and quick reply doesnt have code inserts

[EscSequenceAlpha]

I can start with difficult == 3 if In put it in at the start but it doesnt increase if I input 1 or 2 at the start

the "Congratulations, you are ready to go to the next level!" prints if you score 75% but the difficulty++ doesnt seem to work

[JosAH]

SORRY I did quick reply because reply to thread didnt work for minute and quick reply doesnt have code inserts

You can always simply type the characters [code] ... [/code].

kind regards,

Jos

[kjkrum]

Here's one problem:

if (correct >= (10/100) * 75)

In integer math, 10/100 = 0. So the statement is equivalent to:

if (correct >= 0)

I don't think that's what you wanted.

[brynpttrsn]

static int difficulty;

public static void question(int difficulty)

There are two variables that are called difficulty, one global one, and the one passed into the questions() method.

If you changed

            if( checkComplete(correct, incorrect) == true)
            {
                question(difficulty);
            }

to

            if( checkComplete(correct, incorrect) == true)
            {
                question(this.difficulty);
            }

It would work, but this is a quick fix and probably isn't the best thing to do.
You should probably only have one difficulty variable.