[Solved] [Java] Error in Code & How to Improve My Code..?

Question

I'm just practicing what I've learned in Java so far and I came up with a problem then solved it.

So, the reason for this post is:
1.) I'm having two errors when I run it and I can't seem to find the issue.
2.) I was wondering if there are better ways to go about what I did and if so, how?

Please note:
- I've only completed the arrays part in the tutorial and thus may not know some of the more advanced ways you would normally use.
- I tried organizing it using more classes but it only seemed to make it more disorganized/less efficient. So I went back to my original version that I've linked to this post.

Code: https://pastebin.com/1cHWQcT3
Java Error: https://pastebin.com/UUd2tjB1

Answer 1

Your for loop isn't correct for how you are using it. i will contain 30, 60, 85, 50, 90, 40, 90, 75, 99, 54 in order.
Replace:
for (int i: grades)
with:
for (int i = 0; i < grades.length; i++)

Answer 2

I have it running here. Your totals per grade used the old for loop i correctly.
https://code.sololearn.com/c1KONsgN4p3M

Answer 3

https://code.sololearn.com/c22l8F2nKOan/?ref=app

what above sir describe you
about for each loop
.
you have to understand that..

i correct your program
let me if you not understand
happy coding(-_-)

Answer 4

Your count increments are using i which never gets above F use grades[i] to fix it. I will have a hugh improvement code for you to learn from soon.

Answer 5

Here is how I'd code this:
https://code.sololearn.com/cV3E3e5A9lAE

Answer 6

@John Wells, ohh okay. Thanks a ton.

Thanks for your improved version as well. I don't fully understand it yet with my current knowledge but I'll save it and look at it later.

-------------------------------------------------------
@Arun Tomar, thank you for your replies as well.

Unfortunately, I am having trouble understanding you. I understand it's very hard to explain something in a second language, so I'm definitely not criticizing you. Just that I don't understand very well. Sorry.

Answer 7

@John Wells, thank you for your response.

Why wouldn't an enhanced for loop work for this situation?
In addition, strangely, changing that loop does fix the errors but outputs:
...
There is 0 A grade.
There is 0 B grade.
There is 0 C grade.
There is 0 D grade.
There are 10 F grades.
Yet your link appears to be the same and outputs:
...
There are 3 A grades.
There is 1 B grade.
There is 1 C grade.
There is 1 D grade.
There are 4 F grades.

What am I missing? Why are the outputs different? I only changed the for loop like you said to.

Code: https://pastebin.com/Avz1T4Tu

Answer 8

@Donna, I tried your comment as well. It does fix the error but has the same result as I told John Wells about.
New Code: https://pastebin.com/ACeS8g8E (All in Main class)

Using Eclipse, it outputs:
...
There is 0 A grade.
There is 0 B grade.
There is 0 C grade.
There is 0 D grade.
There are 10 F grades.

What it should output:
There are 3 A grades.
There is 1 B grade.
There is 1 C grade.
There is 1 D grade.
There are 4 F grades.

Why are the outputs different?

Answer 9

Tommy@
you also change in..
if
else if
statement

see in my code or john wells code.
yoi got your ans

Answer 10

Tommy updated to add comments to explain things some.