2.3.2.1.1 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 Section 22.1.3.1.1 (Printing Integers).