Thank you!

Please, use spoiler flag next time.

Both tests are ok, you misunderstood the instructions somehow. Read them again, you'll see it's all there.

And is that Rust?

Read the description again:

a,b are the sizes of the squares

So, one square size is a x a and another is b x b. They're not two rectangles of a x b

For example? Print the input, show us which cases you think are wrong and state the language you tried. Otherwise we can't do anything.