关于uint8_t等类型的定义
C++标准约定：
- 某些整数类型的名称可以缩写，而不需要指定符号类型(signed)和变量类型(int)，只需要指定非斜体部分来标识类型。斜体部分是可选的。
- 如signed short int可以被缩写为signed short, short int, short等
- 具体的大小取决于编译器的实现
- 每组变量的第一个类型是最小的，最后一个是最大的，每个类型至少与同一组中前面的类型一样大。
- char类型一定为1字节
与无符号类型相比，有符号类型的正值范围大约减半，因为其中一位被用于符号的标识
现将stdint.h(C 标准库头文件)内容贴于下方，以便学习。
//
// stdint.h
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
// The C Standard Library <stdint.h> header.
//
#pragma once
#define _STDINT
#ifndef RC_INVOKED
#include <vcruntime.h>
typedef signed char int8_t;
typedef short int16_t;
typedef int int32_t;
typedef long long int64_t;
typedef unsigned char uint8_t;
typedef unsigned short uint16_t;
typedef unsigned int uint32_t;
typedef unsigned long long uint64_t;
typedef signed char int_least8_t;
typedef short int_least16_t;
typedef int int_least32_t;
typedef long long int_least64_t;
typedef unsigned char uint_least8_t;
typedef unsigned short uint_least16_t;
typedef unsigned int uint_least32_t;
typedef unsigned long long uint_least64_t;
typedef signed char int_fast8_t;
typedef int int_fast16_t;
typedef int int_fast32_t;
typedef long long int_fast64_t;
typedef unsigned char uint_fast8_t;
typedef unsigned int uint_fast16_t;
typedef unsigned int uint_fast32_t;
typedef unsigned long long uint_fast64_t;
typedef long long intmax_t;
typedef unsigned long long uintmax_t;
// These macros must exactly match those in the Windows SDK's intsafe.h.
#define INT8_MIN (-127i8 - 1)
#define INT16_MIN (-32767i16 - 1)
#define INT32_MIN (-2147483647i32 - 1)
#define INT64_MIN (-9223372036854775807i64 - 1)
#define INT8_MAX 127i8
#define INT16_MAX 32767i16
#define INT32_MAX 2147483647i32
#define INT64_MAX 9223372036854775807i64
#define UINT8_MAX 0xffui8
#define UINT16_MAX 0xffffui16
#define UINT32_MAX 0xffffffffui32
#define UINT64_MAX 0xffffffffffffffffui64
#define INT_LEAST8_MIN INT8_MIN
#define INT_LEAST16_MIN INT16_MIN
#define INT_LEAST32_MIN INT32_MIN
#define INT_LEAST64_MIN INT64_MIN
#define INT_LEAST8_MAX INT8_MAX
#define INT_LEAST16_MAX INT16_MAX
#define INT_LEAST32_MAX INT32_MAX
#define INT_LEAST64_MAX INT64_MAX
#define UINT_LEAST8_MAX UINT8_MAX
#define UINT_LEAST16_MAX UINT16_MAX
#define UINT_LEAST32_MAX UINT32_MAX
#define UINT_LEAST64_MAX UINT64_MAX
#define INT_FAST8_MIN INT8_MIN
#define INT_FAST16_MIN INT32_MIN
#define INT_FAST32_MIN INT32_MIN
#define INT_FAST64_MIN INT64_MIN
#define INT_FAST8_MAX INT8_MAX
#define INT_FAST16_MAX INT32_MAX
#define INT_FAST32_MAX INT32_MAX
#define INT_FAST64_MAX INT64_MAX
#define UINT_FAST8_MAX UINT8_MAX
#define UINT_FAST16_MAX UINT32_MAX
#define UINT_FAST32_MAX UINT32_MAX
#define UINT_FAST64_MAX UINT64_MAX
#ifdef _WIN64
#define INTPTR_MIN INT64_MIN
#define INTPTR_MAX INT64_MAX
#define UINTPTR_MAX UINT64_MAX
#else
#define INTPTR_MIN INT32_MIN
#define INTPTR_MAX INT32_MAX
#define UINTPTR_MAX UINT32_MAX
#endif
#define INTMAX_MIN INT64_MIN
#define INTMAX_MAX INT64_MAX
#define UINTMAX_MAX UINT64_MAX
#define PTRDIFF_MIN INTPTR_MIN
#define PTRDIFF_MAX INTPTR_MAX
#ifndef SIZE_MAX
#define SIZE_MAX UINTPTR_MAX
#endif
#define SIG_ATOMIC_MIN INT32_MIN
#define SIG_ATOMIC_MAX INT32_MAX
#define WCHAR_MIN 0x0000
#define WCHAR_MAX 0xffff
#define WINT_MIN 0x0000
#define WINT_MAX 0xffff
#define INT8_C(x) (x)
#define INT16_C(x) (x)
#define INT32_C(x) (x)
#define INT64_C(x) (x ## LL)
#define UINT8_C(x) (x)
#define UINT16_C(x) (x)
#define UINT32_C(x) (x ## U)
#define UINT64_C(x) (x ## ULL)
#define INTMAX_C(x) INT64_C(x)
#define UINTMAX_C(x) UINT64_C(x)
#endif // RC_INVOKED
/*
* Copyright (c) 1992-2012 by P.J. Plauger. ALL RIGHTS RESERVED.
* Consult your license regarding permissions and restrictions.
V6.00:0009 */
