在32的stdint.h中有这么一段定义:typedef signed int int_fast8_t;
typedef signed int int_fast16_t;
typedef signed int int_fast32_t;
typedef signed __int64 int_fast64_t;
/* fastest minimum-width unsigned integer types */
typedef unsigned int uint_fast8_t;
typedef unsigned int uint_fast16_t;
typedef unsigned int uint_fast32_t;
typedef unsigned __int64 uint_fast64_t;
从上可以看到,int_fast8_t,int_fast16_t和int_fast32_t的数据类型其实都是signed int ,uint_fast8_t,uint_fast16_t和uint_fast32_t的数据类型都是unsigned int,为什么这样定义了。
int_fast8_t和uint_fast8_t数据类型的意义又何在? |