Integer (integer.h)

Integer is a class that provides a arbitrary precision integer arithmetic. We can use this class Integer like a signed built-in type, e.g. int, without length restriction.

We support only one built-in type Digit, because of efficiency and portability. But Digit is an unsigned built-in type. For that reason we cannot support expressions like a = -1 and C++ translate internally -1 to $2^\beta-1$, the largest possible unsigned built-in number.