I don't know why people mark this as clever, to me it's clearly best practices as I'd prefer this code over other answers in production because it's clean and small enough to grasp immediately. Though you missed +1 at list generation:

(i) => interval[0] + i // all elements will be smaller than actual ones in the interval by one

which should be as the following:

(i) => interval[0] + 1 + i

But it doesn't really matter, the code works correctly and it's fine.

just curious,would it work for a single array with extreme values??

slow but clearly

clever but slow

Thank you!!!!
I had no idea what was going on and I was going crazy.
Hopefully, it will be correct this time.

Now there are failed tests. Check the Dart version selected, versions are reset sometimes.

The translation seems to be unpublished now.

It was a mistake, now it should be ok.
Thank you.

int getCount(String$ inputStr)

What is that $?