C++:What is the difference between "unsigned int i" and "int i" ?

Question

Saw this in a challenge question as well as in a written program. What does the "unsigned" mean ?

Answer 1

unsigned means it cannot be a negative number .
int, can be negative or positive number.

Answer 2

bahha is right
and what’s more
the range is different，too
int :-2^31 ~ 2^31
unsigned int:0~2^32

Answer 3

Celestino🇰🇪🇫🇷 What do you mean by "sure??"?

https://stackoverflow.com/questions/9045436/the-real-difference-between-int-and-unsigned-int

Answer 4

A-Z