Hexadecimal integer literals

A hexadecimal integer literal begins with the 0 digit followed by either an x or X, followed by any combination of the digits 0 through 9 and the letters a through f or A through F. The letters A (or a) through F (or f) represent the values 10 through 15, respectively.

Hexadecimal integer literal syntax

Read syntax diagramSkip visual syntax diagram0x0Xdigit_0_to_fdigit_0_to_F
The following are examples of hexadecimal integer literals: 
0x3b24 
0XF96 
0x21 
0x3AA 
0X29b 
0X4bD