Fundamental types

 

C++

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C + +語言

大會的主題 Original: General topics The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
預處理器 評論 關鍵字	ASCII表 轉義序列 C + +的歷史
流量控制 Original: Flow control The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
條件執行語句 Original: Conditional execution statements The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
if statement	switch statement
迭代語句 Original: Iteration statements The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
for loop range-for loop （C++11）	while loop do-while loop
跳轉語句 Original: Jump statements The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
continue statement break statement	goto statement return statement
功能 Original: Functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
函數聲明
lambda函數的聲明
函數模板
的歷史。內嵌說明
異常規範 （過時了）
noexcept說明 （C++11）
例外 Original: Exceptions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
扔表達	try-catch塊
命名空間 Original: Namespaces The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
命名空間聲明	命名空間的別名
類型 Original: Types The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
基本類型 複合類型 枚舉類型	聯合類型 函數類型
decltype specifier （C++11）
規範 Original: Specifiers The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
CV符
存儲時間說明符
constexpr說明 （C++11）
汽車符 （C++11）
alignas說明 （C++11）
初始化 Original: Initialization The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
默認的初始化 值初始化 零初始化 複製初始化 直接初始化	集合初始化 表初始化 （C++11） 常數初始化 參考電壓的初始化

常 Original: Literals The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
整數文字 字元文字 浮點文字 字元串文字	布爾文字 nullptr （C++11） 用戶定義的 （C++11）
表達式 Original: Expressions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
價值類型 為了評價	運營商 運算符的優先順序
另一種表示形式
實用工具 Original: Utilities The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
類型 Original: Types The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
typedef declaration
聲明類型別名 （C++11）
屬性 （C++11）
施放 Original: Casts The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
隱式轉換
const_cast conversion
static_cast conversion
dynamic_cast conversion
reinterpret_cast conversion
C-風格和功能轉換
內存分配 Original: Memory allocation The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
new expression	delete expression
類 Original: Classes The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
類的聲明 this pointer 訪問符	朋友說明 初始化列表
類特定的功能特性 Original: Class-specific function properties The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
虛函數 覆蓋說明 （C++11） 最後說明 （C++11）	明確的 （C++11） 靜態的
特殊的成員函數 Original: Special member functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
默認構造函數 拷貝構造函數 移動的構造函數 （C++11）	複製的任務 移動分配 （C++11） 析構函數
模板 Original: Templates The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
類模板
函數模板
模板特化
參數包 （C++11）
雜項 Original: Miscellaneous The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
內聯彙編

 

(Also see the list of type-related utilities that are provided by C++.)

Boolean type

bool - type, capable of holding one of the two values: true or false.

Character types

signed char - type for signed character representation.

unsigned char - type for unsigned character representation.

char - type for character representation which can be most efficiently processed on the target system (equivalent to either signed char or unsigned char).

wchar_t - type for wide character representation

char16_t - type for UTF-16 character representation （C++11 起）

char32_t - type for UTF-32 character representation （C++11 起）

Integer types

int - basic integer type. Can be omitted if any of the modifiers are present. If no length modifiers are present, guaranteed to have width of at least 16 bits. However, on 32/64 bit systems it is almost exclusively guaranteed to have width of at least 32 bits (see below).

修飾符

Modifies the integer type. Can be mixed in any order. Only one of each group can be present in type definition.

Signedness

signed - target type will have signed representation (this is the default if omitted)

unsigned - target type will have unsigned representation

Size

short - target type will be optimized for space and will have width of at least 16 bits.

long - target type will have width of at least 32 bits.

long long - target type will have width of at least 64 bits （C++11 起）

Properties

The following table summarizes all available integer types and their properties:

Type specifier	Equivalent type	Width in bits by data model
		C++ standard	LP32	ILP32	LLP64	LP64
short	short int	at least 16	16	16	16	16
short int
signed short
signed short int
unsigned short	unsigned short int
unsigned short int
int	int	at least 16	16	32	32	32
signed
signed int
unsigned	unsigned int
unsigned int
long	long int	at least 32	32	32	32	64
long int
signed long
signed long int
unsigned long	unsigned long int
unsigned long int
long long	long long int （C++11）	at least 64	64	64	64	64
long long int
signed long long
signed long long int
unsigned long long	unsigned long long int （C++11）
unsigned long long int

Note: the C++ Standard guarantees that 1 == sizeof(char) <= sizeof(short) <= sizeof(int) <= sizeof(long) <= sizeof(long long).

Data models

32 bit systems:

• LP32:

• Win16 API

• ILP32;

• Win32 API
• Unix and Unix-like systems (Linux, Mac OS X)

64 bit systems:

• LLP64

• Win64 API

• LP64

• Unix and Unix-like systems (Linux, Mac OS X)

Floating point types

float - single precision floating point type. Usually IEEE-754 32 bit floating point type

double - double precision floating point type. Usually IEEE-754 64 bit floating point type

long double - extended precision floating point type. Does not necessarily map to types mandated by IEEE-754. Usually 80-bit x87 floating point type on x86 and x86-64 architectures.

Range of values

The following table provides a reference for limits of common numeric representations. Note, that all popular data models (including all of ILP32, LP32, LP64, LLP64) use two's complement arithmetic. Also, the C++ Standard does not specify which arithmetic would be used, thus it guarantees only the limits of one's complement arithmetic.

Type	Size in bits	Format	Value range
			Approximate	Exact
character	8	signed (one's complement)	-127 to 127
		signed (two's complement)	-128 to 127
		unsigned	0 to 255
integral	16	signed (one's complement)	± 3.27 · 104	-32767 to 32767
		signed (two's complement)		-32768 to 32767
		unsigned	0 to 6.55 · 104	0 to 65535
	32	signed (one's complement)	± 2.14 · 109	-2,147,483,647 to 2,147,483,647
		signed (two's complement)		-2,147,483,648 to 2,147,483,647
		unsigned	0 to 4.29 · 109	0 to 4,294,967,295
	64	signed (one's complement)	± 9.22 · 1018	-9,223,372,036,854,775,807 to 9,223,372,036,854,775,807
		signed (two's complement)		-9,223,372,036,854,775,808 to 9,223,372,036,854,775,807
		unsigned	0 to 1.84 · 1019	0 to 18,446,744,073,709,551,615
floating point	32	IEEE-754	± 3.4 · 10± 38 (~7 digits)	min subnormal: ± 1.401,298,4 · 10-47 min normal: ± 1.175,494,3 · 10-38 max: ± 3.402,823,4 · 1038
	64	IEEE-754	± 1.7 · 10± 308 (~15 digits)	min subnormal: ± 4.940,656,458,412 · 10-324 min normal: ± 2.225,073,858,507,201,4 · 10-308 max: ± 1.797,693,134,862,315,7 · 10308

關鍵字

bool, true, false, char, wchar_t, char16_t, char32_t, int, short, long, signed, unsigned, float, double

另請參閱

• <div class="t-tr-text"> CV符
  Original:

  cv specifiers

  The text has been machine-translated via [http://translate.google.com Google Translate].
  You can help to correct and verify the translation. Click [http://en.cppreference.com/w/Cppreference:MachineTranslations here] for instructions.
  </div>,
• <div class="t-tr-text"> 存儲時間說明符
  Original:

  storage duration specifiers

  The text has been machine-translated via [http://translate.google.com Google Translate].
  You can help to correct and verify the translation. Click [http://en.cppreference.com/w/Cppreference:MachineTranslations here] for instructions.
  </div>