C语言基础 -56 构造类型_枚举类型的定义及使用

book@100ask:~/C_coding/CH02$ cat enum.c
#include <stdio.h>
#include <stdlib.h>

enum day
{
	MON,
	TUS,
	WES,
	THR,
	FRI,
	SAT,
	SUN
};

int main()
{
	enum day a = MON;
	printf("%d\n",a);
}
book@100ask:~/C_coding/CH02$ make enum
cc     enum.c   -o enum
book@100ask:~/C_coding/CH02$ ./enum
0 
// 同时只有一个元素生效，排序默认从0开始，按顺序排列

book@100ask:~/C_coding/CH02$ cat enum.c
#include <stdio.h>
#include <stdlib.h>

enum day
{
	MON,
	TUS,
	WES,
	THR,
	FRI,
	SAT,
	SUN
};

int main()
{
	enum day a = FRI;
	printf("%d\n",a);
}
book@100ask:~/C_coding/CH02$ make enum
cc     enum.c   -o enum
book@100ask:~/C_coding/CH02$ ./enum
4

book@100ask:~/C_coding/CH02$ cat enum.c
#include <stdio.h>
#include <stdlib.h>

enum day
{
	MON = 1,    // 自定义MON=1，则从1开始排序
	TUS,
	WES,
	THR,
	FRI,
	SAT,
	SUN
};

int main()
{
	enum da