Undefined behavior in c/c++: i++ + ++i vs ++i + i++ [duplicate]

Answer 1

int i = 1;
int j = i++ + ++i;

Evaluation will happen from Right to left, i.e. firstly ++i will be processed then i++. So j will have value 4.

You will get a warning that "operation on 'i' may be undefined" but there is no problem with this expression.