c语言基础，\r, \n, \r\n

Enumeration (or enum) in C

Enumeration (or enum) is a user defined data type in C. It is mainly used to assign names to integral constants, the names make a program easy to read and maintain.

enum State {Working = 1, Failed = 0};

定义枚举类型：

Variables of type enum can also be defined. They can be defined in two ways:

// In both of the below cases, "day" is
// defined as the variable of type week. 

enum week{Mon, Tue, Wed};
enum week day;

// Or

enum week{Mon, Tue, Wed}day;

https://www.geeksforgeeks.org/enumeration-enum-c/

//在linux系统下,printf函数是行缓冲式的输出,当printf遇到\n时,或者缓冲区满时,才会将缓冲区里的内容刷新到标准输出(stdout).

\r = CR (Carriage Return) // Used as a new line character in Mac OS before X

\n = LF (Line Feed) // Used as a new line character in Unix/Mac OS X

\r\n = CR + LF // Used as a new line character in Windows

#include <stdio.h>//这一行不加也可以，但是会有警告。
enum State {Working = 1, Failed = 0};
int main(){
    enum State s;
    s = Working;
    printf("%daaaaaa\r123", s);
//    fflush(stdout);
    return 0;
}

　　

\n是另起一行，\r的话回到本行的开头，如果继续输入的话会把先前的覆盖掉

比如printf("asdflkj\r111")输出的是111flkj