Question

An unsigned int can be twice as large as the side int,explain how

Answer 1

Answer:

A signed int uses a bit to store the sign.

In an unsigned int, that bit is available to be an extra power of 2, so the number can be twice as large.

Another way of thinking of it is that the number of values is fixed.  With a signed int, those values are distributed half-and-half between negative and non-negative.  While with unsigned int, they're all non-negative, so there are twice as many non-negative values.