What happen when we exceed valid range of built-in data types

Question

You will understand what mean please see the code👇
https://code.sololearn.com/cHh2gHBoj8vm/?ref=app

Answer 1

In C/C++ values are represented as binary numbers and not checked for invalid ranges. This means that the signed 8 bit value 127 plus one is -128 because the addition causes an integer overflow.

Answer 2

Signed integer overflows evoke undefined behavior, while unsigned overflows are mathematically defined (they wrap around).