C: an array of characters and strings

String array of characters

• No C language string data type that can be replaced by an array of char;
• An array of a char string must be, but is not necessarily an array of char string;
• The number 0 (and the character '\ 0' is equivalent) is a char array at the end of the string, but if char array not end in a number 0, then it is not a string, just an ordinary character array, so the string is a special an array of char.

#include <stdio.h>

int main()
{
    char c1[] = { 'c', ' ', 'p', 'r', 'o', 'g' }; //普通字符数组
    printf("c1 = %s\n", c1); //乱码，因为没有’\0’结束符

    //以‘\0’(‘\0’就是数字0)结尾的字符数组是字符串
    char c2[] = { 'c', ' ', 'p', 'r', 'o', 'g', '\0'}; 
    printf("c2 = %s\n", c2);

    //字符串处理以‘\0’(数字0)作为结束符，后面的'h', 'l', 'l', 'e', 'o'不会输出
    char c3[] = { 'c', ' ', 'p', 'r', 'o', 'g', '\0', 'h', 'l', 'l', 'e', 'o', '\0'};
    printf("c3 = %s\n", c3);

    return 0;
}

Initialization string:

#include <stdio.h>

// C语言没有字符串类型，通过字符数组模拟
// C语言字符串，以字符‘\0’, 数字0
int main()
{
    //不指定长度, 没有0结束符，有多少个元素就有多长
    char buf[] = { 'a', 'b', 'c' };
    printf("buf = %s\n", buf);  //乱码

    //指定长度，后面没有赋值的元素，自动补0
    char buf2[100] = { 'a', 'b', 'c' };
    printf("buf2 = %s\n", buf2);

    //所有元素赋值为0
    char buf3[100] = { 0 };

    //char buf4[2] = { '1', '2', '3' };//数组越界

    char buf5[50] = { '1', 'a', 'b', '0', '7' };
    printf("buf5 = %s\n", buf5);

    char buf6[50] = { '1', 'a', 'b', 0, '7' };
    printf("buf6 = %s\n", buf6);
        char buf7[50] = { '1', 'a', 'b', '\0', '7' };
    printf("buf7 = %s\n", buf7);

    //使用字符串初始化，编译器自动在后面补0，常用
    char buf8[] = "agjdslgjlsdjg";

    //'\0'后面最好不要连着数字，有可能几个数字连起来刚好是一个转义字符
    //'\ddd'八进制字义字符，'\xdd'十六进制转移字符
    // \012相当于\n
    char str[] = "\012abc";
    printf("str == %s\n", str);

    return 0;
}

Scanf string received using:

#include <stdio.h>

int main()
{
    char str[100];
   
    printf("input string1 : \n");
    scanf("%s", str);//scanf(“%s”,str)默认以空格分隔
    printf("output:%s\n", str);

    return 0;
}