Answer 1

Confuse question? Is it not your own code? Your own output statements?

Between, there remove any space space after System.in

Use this statement :
Scanner sc = new Scanner(System.in);
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I and many commented about the errors already..
read all properly to know about errors...

Answer 2

Prakhar Khanduri
You mean like: display prompt message for l, accept input then ask another input b, and accept it, .....

Now I understood your question. You are expecting an interactive environment. But sololearn (Or any online compliers, almost) are not interactive.

on pop- up window here, enter values
ex:
24 3
and hit submit button, you can see output...

If your program needs multiple inputs ,then give all required inputs for code in pop up by space separated or in new line in required order at a time in pop-up box.. This is only difference with other IDEs. Code work is same anyways...

This explains how solo learn input console works...
https://code.sololearn.com/WhiNb9BkJUVC/?ref=app