C++关键词(一)之基础类型

1 基础类型统计

关键字 数据类型 范围 备注
bool 布尔值 [true,false]
char 有符号字符型 [-128,127] 等价于signed char
unsigned char 无符号字符型 [0,255]
short 有符号短整型 [-32768,32767] 等价于signed short
unsigned short 无符号的短整型 [0,65535]
int 有符号整型 [-2147483648,2147483647] 等价于signed int
unsigned int 无符号整型 [0,4294967295]
long 有符号长整型 [-9223372036854775808,9223372036854775807]
unsigned long 无符号长整型 [0,18446744073709551615]
long long 有符号超长整型 [-9223372036854775808,9223372036854775807]
unsigned long long 无符号超长整型 [0,18446744073709551615]
float 单精度浮点型 [1.17549e-38,3.40282e+38]
double 双精度浮点型 [2.22507e-308,1.79769e+308]
long double 长浮点型 [3.3621e-4932,1.18973e+4932]

2.测试代码

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#include  iostream>
#include  limits.h>
#include  limits>
int main(int argc,char * argv[])
{
    //limit.h
    std::cout << "--------------C Style---------------"  <<std::endl;
    std::cout << "bool           :["  "true,false]" << std::endl;

    std::cout << "signed char    :[" << SCHAR_MIN << "," << SCHAR_MAX  "]"  <<std::endl;
    std::cout << "unsigned char  :[" << CHAR_MIN << "," << UCHAR_MAX  "]" << std::endl;

    std::cout << "short          :[" << SHRT_MIN << ","  <<SHRT_MAX  "]" << std::endl;
    std::cout << "unsigned short :[" << 0 << "," << USHRT_MAX  "]" << std::endl;

    std::cout << "int            :[" << INT_MIN  <<"," << INT_MAX  "]" << std::endl;
    std::cout<<  "unsigned int   :["  0  "," << UINT_MAX  <<"]"  <<std::endl;

    std::cout << "long           :[" << LONG_MIN << "," << LONG_MAX << "]" << std::endl;
    std::cout << "unsigned long  :["  <<0  <<"," << ULONG_MAX << "]" << std::endl;

    std::cout  <<"long long      :[" << LONG_LONG_MIN  "," << LONG_LONG_MAX  <<"]"  <<std::endl;
    std::cout  <<"unsigned long long :[" << 0  <<","  <<ULONG_LONG_MAX  <<"]"<<  std::endl;


    std::cout  "--------------C++ Style---------------"  std::endl;
    std::cout  "char            :[" << int(std::numeric_limits char>::min()) << "," << int(std::numeric_limits <char>::max()) << "]" << std::endl;
    std::cout  "unsigned char   :[" <<int(std::numeric_limits unsigned char>::min())<<  ","<<  int(std::numeric_limits <unsigned char>::max())  <<"]" << std::endl;

    std::cout  "short           :[" << std::numeric_limits<short>::min() << "," << std::numeric_limits< short>::max() << "]"  <<std::endl;
    std::cout  "unsigned short  :[" << std::numeric_limits< unsigned short>::min() << "," << std::numeric_limits<unsigned short>::max()<<  "]" << std::endl;

    std::cout  "int             :[" << std::numeric_limits <int>::min()<<  "," << std::numeric_limits <int>::max() <<"]"<<  std::endl;
    std::cout  "unsigned int    :[" << std::numeric_limits< unsigned int>::min() << "," << std::numeric_limits< unsigned int>::max() << "]" << std::endl;

    std::cout  "long            :[" << std::numeric_limits< long>::min() << "," << std::numeric_limits <long>::max() << "]"<<  std::endl;
    std::cout  "unsigned long   :[" << std::numeric_limits< unsigned long>::min()<<  "," << std::numeric_limits <unsigned long>::max() << "]" << std::endl;

    std::cout  "long long       :[" << std::numeric_limits <long long>::min() << "," << std::numeric_limits <long long>::max() << "]" << std::endl;
    std::cout  "unsigned long long:["<<  std::numeric_limits< unsigned long long>::min() << "," << std::numeric_limits <unsigned long long>::max() << "]" << std::endl;


    std::cout  "float           :[" << std::numeric_limits <float>::min() << ","  <<std::numeric_limits< float>::max() << "]"<<  std::endl;
    std::cout  "double          :[" << std::numeric_limits <double>::min()<<  ","  <<std::numeric_limits< double>::max() << "]" << std::endl;

    std::cout  "long double     :[" << std::numeric_limits <long double>::min() << "," << std::numeric_limits <long double>::max() << "]" << std::endl;

    return 0;
}

3.程序输出

--------------C Style---------------     
bool           :[true,false]
signed char    :[-128,127]
unsigned char  :[0,255]
short          :[-32768,32767]
unsigned short :[0,65535]
int            :[-2147483648,2147483647]
unsigned int   :[0,4294967295]
long           :[-9223372036854775808,9223372036854775807]
unsigned long  :[0,18446744073709551615]
long long      :[-9223372036854775808,9223372036854775807]
unsigned long long :[0,18446744073709551615]
--------------C++ Style---------------
char            :[-128,127]
unsigned char   :[0,255]
short           :[-32768,32767]
unsigned short  :[0,65535]
int             :[-2147483648,2147483647]
unsigned int    :[0,4294967295]
long            :[-9223372036854775808,9223372036854775807]
unsigned long   :[0,18446744073709551615]
long long       :[-9223372036854775808,9223372036854775807]
unsigned long long:[0,18446744073709551615]
float           :[1.17549e-38,3.40282e+38]
double          :[2.22507e-308,1.79769e+308]
long double     :[3.3621e-4932,1.18973e+4932]