For those who did the java course

Question

the shapes problem is broken right?. Test case #3 keeps yelling at me.

I've seen lots of profiles and seems like nobody have solved it. Everyone got 99% of the java course

Answer 1

Your problem is: width * width * Math.PI(makes a wrong output)

It should be: Math.PI * width * width

Answer 2

If you not solved or any difficulty in solving, can you share your attempt..

Answer 3

Yes. As already said use
System.out.print(Math.PI*width*width);
Instead of
System.out.print(width*width*Math.PI);

Answer 4

Michel Beṭar It produces a double no matter what, but for some reason, the decimals are not completely identical in that output.

Answer 5

No, can confirm its not broken. I just solved it to verify the issue but everything worked as expected

Answer 6

Jayakrishna🇮🇳 - If you not solved or any difficulty in solving, can you share your attempt..

https://code.sololearn.com/c2ec2e567oWT/?ref=app

I don't if you can see private code bits having the link. If you cannot see it ask me to make it public

Answer 7

Jayakrishna🇮🇳 thank you also

Answer 8

This is floating point arithmetic at it's finest. Michel Beṭar your solution should actually be more accurate! Take at the IEEE floating point standard.

I really think sololearn should have a threshhold here for the correct solution. Maybe if it is correct it to 4 digits or something

Answer 9

I made a small program to experiment around a bit. Most of the time width*width*PI is most accurate: int multiplication is perfect(except for int overflows). float mutiplication almost alwas has an error this is due to a limitation in the notation/storage.
So if you only do one float multiplication, the error should be smaller in most cases.
If you want to experiment around yourself:

https://code.sololearn.com/cz50tEnrRbRi/?ref=app

Answer 10

Quantum oh so adding Math.PI in the begging so java already knows the output will be a double?