#include <stdio.h>
int main()
{
    char ch;
    printf("请输入一个字符：");
    scanf("%c", &ch);

    if (ch >= '0' && ch <= '9')
    {
        printf("这是数字字符\n");
    }
    else if (ch >= 'A' && ch <= 'Z')
    {
        printf("这是大写字母\n");
    }
    else if (ch >= 'a' && ch <= 'z')
    {
        printf("这是小写字母\n");
    }
    else if (ch == ' ')
    {
        printf("这是空格\n");
    }
    else
    {
        printf("这是其他字符\n");
    }
    return 0;
}