Is this code correct or not

Question

https://code.sololearn.com/cX7NG8IQnGKg/?ref=app

Answer 1

in simple words

you cant apply decrement on rvalue.
by rvalue i mean something which evaluates to expression which dont have an identifier.

like
int x=0;
int y=--x; //valid since x is lvalue
y=--5; // invalid since 5 is rvalue

aside : [many say rvalue is something which doesn't have a memory address but its wrong , as every single constant expression has memory address associated with it , its that there's no simple way to know its memory address, i.e you will find rvalue in final compiled binary so it must live somewhere in memoy ]