2.3.2.2 Syntax of an Integer

Integers can be written as a sequence of digits, optionally preceded by a sign and optionally followed by a decimal point; see Figure~2–9. When a decimal point is used, the digits are taken to be in radix 10; when no decimal point is used, the digits are taken to be in radix given by the current input base.

For information on how integers are printed, see Printing Integers.