C语言：枚举类型

#include <stdio.h>
enum _bool {false,true};
int main(){
        enum colors {
                red,
                orange,
                yellow,
                green,
                blue,
                violet,
        };

        enum colors a = green;
        int b = yellow;
        printf("%d\n",a);
        printf("%d\n",b);
}