C语言显示字符型和整型数据类型的表示范围

#include <stdio.h> 
#include <limits.h>

int main(void)
{
  puts("该环境下各字符型、整型数值的范围");
  printf("char:           :%d~%d\n",   CHAR_MIN,   CHAR_MAX);
  printf("signed char     :%d~%d\n",   SCHAR_MIN,  SCHAR_MAX);
  printf("unsignd char    :%d~%d\n",   0,          UCHAR_MAX);
  
  printf("short           :%d~%d\n",   SHRT_MIN,   SHRT_MAX);
  printf("int             :%d~%d\n",   INT_MIN,    INT_MAX);
  printf("long            :%ld~%ld\n", LONG_MIN,   LONG_MAX);
  
  printf("unsigned short  :%u~%u\n",   0,          USHRT_MAX);
  printf("usigned         :%u~%u\n",   0,          UINT_MAX);
  printf("unsigned long   :%lu~%lu\n", 0,          ULONG_MAX);
  
  return 0;
}

运行结果：

数据类型	最小值	最大值
char	-128	127
signed char	-128	127
unsignd char	0	255
short	-32768	32767
int	-2147483648	2147483647
long	-2147483648	2147483647
unsigned short	0	65535
usigned	0	4294967295
unsigned long	0	4294967295

声明变量时，可以通过加上 类型说明符 signed 或 unsigned 来指定其中一种数据类型。若不加类型说明符，则默认为有符号。

无符号整型 （unsigned integer type） 表示 0 和整数的整型
有符号整型 （signed integer type） 表示 0 和正负数的整型

字符型	整型	有符号整型	无符号整型
signed char	signed short int	signed char	unsigned char
char	signed int	signed short int	unsigned short int
unsigned char	signed long int	signed int	unsigned int
	unsigned short int	signed long int	unsigned long int
	unsigned int
	unsigned long int
	signed short
	signed int
	short
	unsigned short
	signed
	int
	unsigned
	signed long
	long int
	long
	unsigned long

注：char 型比较特殊，存在既不带 signed 又不带 unsigned 的 “单独”的char型。
对于单独的 short 和 long, 可以认为是省略了 int。
对于单独的 signed 和 unsigned,可以认为是（非 short 和 long 的）int。