Integer literals 整型字面量

An integer literal is a sequence of digits representing an integer constant. An optional prefix sets a non-decimal base: 0 for octal, 0x or 0X for hexadecimal. In hexadecimal literals, letters a-f and A-F represent values 10 through 15.

整型字面量是一个数字序列代表整型常量.非十进制必须以0(八进制)、0x或0X(十六进制)开头。十六进制字面量中字符a-f 和A-F 代表10到15.

下面是示例：

int_lit     = decimal_lit | octal_lit | hex_lit .
decimal_lit = ( "1" … "9" ) { decimal_digit } .
octal_lit   = "0" { octal_digit } .
hex_lit     = "0" ( "x" | "X" ) hex_digit { hex_digit } .
42
0600
0xBadFace
170141183460469231731687303715884105727