计算机的内存是以字节byte为单位进行组织的。一个字节是我们能够在c++程序中操作的最小内存单位。
下面我们通过程序打印一下c++中常见的数据类型以及其所能够存储的数据范围。
常见的数据类型可参考下面
cout << "数据类型 " << "字节数 " << "最小范围： " << "最大范围： " << endl;
cout << "char " << sizeof (char) << " " << (numeric_limits<char>::min)() << " " << (numeric_limits<char>::max)() << endl;
cout << "int " << sizeof (int) << " " << numeric_limits<int>::min() << " " << numeric_limits<int>::max() << endl;
cout << "short int " << sizeof (short int) << " " << numeric_limits<short int>::min() << " " << numeric_limits<short int>::max() << endl;
cout << "long int " << sizeof (long int) << " " << numeric_limits<long int>::min() << " " << numeric_limits<long int>::max() << endl;
cout << "float " << sizeof (float) << " " << numeric_limits<float>::min() << " " << numeric_limits<float>::max() << endl;
cout << "double " << sizeof (double) << " " << numeric_limits<double>::min() << " " << numeric_limits<double>::max() << endl;
cout << "long double " << sizeof (long double) << " " << numeric_limits<long double>::min() << " " << numeric_limits<long double>::max() << endl;
cout << "bool " << sizeof (bool) << " " << numeric_limits<bool>::min() << " " << numeric_limits<bool>::max() << endl;
cout << "wchar_t " << sizeof (wchar_t) << " " << numeric_limits<wchar_t>::min() << " " << numeric_limits<wchar_t>::max() << endl;
cout << "long " << sizeof (long) << " " << numeric_limits<long>::min() << " " << numeric_limits<long>::max() << endl;
cout << "long long " << sizeof (long long) << " " << numeric_limits<long long>::min() << " " << numeric_limits<long long>::max() << endl;
//无符号数据类型
cout << "unsigned char " << sizeof (unsigned char) << " " << numeric_limits<unsigned char>::min() << " " << numeric_limits<unsigned char>::max() << endl;
cout << "unsigned int " << sizeof (unsigned int) << " " << numeric_limits<unsigned int>::min() << " " << numeric_limits<unsigned int>::max() << endl;
cout << "unsigned long " << sizeof (unsigned long) << " " << numeric_limits<unsigned long>::min() << " " << numeric_limits<unsigned long>::max() << endl;
cout << "unsigned short " << sizeof (unsigned short) << " " << numeric_limits<unsigned short>::min() << " " << numeric_limits<unsigned short>::max() << endl;
cout << "unsigned long long " << sizeof (unsigned long long) << " " << numeric_limits<unsigned long long>::min() << " " << numeric_limits<unsigned long long>::max() << endl;
数据类型 字节数 最小范围： 最大范围：
char 1 �
int 4 -2147483648 2147483647
short int 2 -32768 32767
long int 8 -9223372036854775808 9223372036854775807
float 4 1.17549e-38 3.40282e+38
double 8 2.22507e-308 1.79769e+308
long double 16 3.3621e-4932 1.18973e+4932
bool 1 0 1
wchar_t 4 -2147483648 2147483647
long 8 -9223372036854775808 9223372036854775807
long long 8 -9223372036854775808 9223372036854775807
unsigned char 1 �
unsigned int 4 0 4294967295
unsigned long 8 0 18446744073709551615
unsigned short 2 0 65535
unsigned long long 8 0 18446744073709551615
上面的结果仅供参考，不同的机器上会有差异存在。
一些基本类型可以使用一个或多个类型修饰符进行修饰：
signed
unsigned
short
long
关于修饰符的更多内容这里就不多说了，不清楚的可以查阅下资料嘚。