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class Fact
	public static void main(String[] args)
		int num=344;
		int num1=num;
		int fact=1;
		int ld=0;
		int factsum=0;
				for(int i=ld;i>=1;i--)

What I have tried:

I have written code to check strong number in java without using methods, I'm unable to execute the code correctly, please help.
Updated 20-Oct-22 10:23am

1 solution

Compiling does not mean your code is right! :laugh:
Think of the development process as writing an email: compiling successfully means that you wrote the email in the right language - English, rather than German for example - not that the email contained the message you wanted to send.

So now you enter the second stage of development (in reality it's the fourth or fifth, but you'll come to the earlier stages later): Testing and Debugging.

Start by looking at what it does do, and how that differs from what you wanted. This is important, because it give you information as to why it's doing it. For example, if a program is intended to let the user enter a number and it doubles it and prints the answer, then if the input / output was like this:
Input   Expected output    Actual output
  1            2                 1
  2            4                 4
  3            6                 9
  4            8                16
Then it's fairly obvious that the problem is with the bit which doubles it - it's not adding itself to itself, or multiplying it by 2, it's multiplying it by itself and returning the square of the input.
So with that, you can look at the code and it's obvious that it's somewhere here:
int Double(int value)
   return value * value;

Once you have an idea what might be going wrong, start using the debugger to find out why. Put a breakpoint on the first line of the method, and run your app. When it reaches the breakpoint, the debugger will stop, and hand control over to you. You can now run your code line-by-line (called "single stepping") and look at (or even change) variable contents as necessary (heck, you can even change the code and try again if you need to).
Think about what each line in the code should do before you execute it, and compare that to what it actually did when you use the "Step over" button to execute each line in turn. Did it do what you expect? If so, move on to the next line.
If not, why not? How does it differ?
Hopefully, that should help you locate which part of that code has a problem, and what the problem is.

This is a skill, and it's one which is well worth developing as it helps you in the real world as well as in development. And like all skills, it only improves by use!
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Amogh 2022 20-Oct-22 16:43pm    
Could you please correct the code?, I guess my logic is correct but something is wrong with the structure or syntax.
OriginalGriff 20-Oct-22 16:52pm    
If it was the syntax, it wouldn't compile.
And if it wouldn't compile, then it wouldn't run.
Since you say it run but not correctly, it's not syntax errors.

So use the debugger: you wrote the code, so you know what you expect it do do at each stage. Use the debugger to find out exactly what it is actually doing, and how that differs from your expectation. My doing that for you teaches you nothing, and makes it harder for you to learn how to fix your problems in later tasks - since they will be more complicated, and hence larger. Learn now, on tiny projects like this and you can use that knowledge on the larger projects as well.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

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