2_C语言中的数据类型 （五）char

#include <stdio.h>

int main01()
{
    char c;//定义一个char类型的变量
    c = ‘a‘;
    printf("%c\n", c);

    //c = 4;//c等于一个整数4
    //c = ‘4‘;//c等于一个字符4
    c = ‘D‘;
    c = c + 32;//将大写字母转化为小写字母的算法
    
    printf("%c\n", c);//52就是‘4’这个字符的ASCII码

    c = ‘9‘;
    //c = c - 48;
    c = c - ‘0‘;//将字符转化为整数的算法
    printf("%d\n", c);
    return 0;
}

int main()
{
    char c = ‘\a‘;
    c = ‘a‘;
    printf("%c", c);

    c = ‘\b‘;
    printf("%c", c);

    c = ‘b‘;
    printf("%c", c);

    c = ‘\n‘;
    printf("%c", c);

    c = ‘a‘;
    printf("%c", c);

    c = ‘b‘;
    printf("%c", c);

    c = ‘\r‘;
    printf("%c", c);

    c = ‘c‘;
    printf("%c", c);

    //c = ‘\r‘;
    //printf("%c", c);

    printf("\n");
    c = ‘a‘;
    printf("%c", c);
    c = ‘\t‘;
    printf("%c", c);
    c = ‘b‘;
    printf("%c", c);

    c = ‘\‘‘;
    printf("%c", c);

    char a = 0;//定义一个有符号的char
    unsigned char b = 0;//定义一个无符号的char
    b = b - 1;

    a = 127;
    a = a + 5;
    printf("%d", a);
    return 0;
}