switch

#include <stdio.h>

int main(int argc, char * argv[])
{
    int i;
    scanf("%d",&i);
    switch(i)
    {
        case 1:
        {printf("春");
            break;
        }
        case 2:
        {
            printf("夏");
            break;
        }
        case 3:
        {
            printf("秋");
            break;
        }

        case 4:
        { printf("冬");
        }
        default:
            break;

}
}

多个case可以运行一个语句块

case中定义变量需要加{}；

枚举类型（enum）

1

提高程序的可读性，本质是整形，用枚举类型代表整数常量；

enum Season

{spring,summer,autumn,winter}//默认从零开始enum Season aeason=0;scanf（"%d,&season"）;switch(season){case spring:{printf("spring");}case summer:

{printf("spring");}case autumn:{printf("autumn");]

}

#include <stdio.h>
enum Season

{
    spring=1,
    summer,
    autumn,
    winter
};
typedef enum Season myseason ;//为现有类型创建一个别名
int main(int argc, char * argv[])
{
        //默认从零开始
    myseason season=0;
    scanf("%d",&season);
    switch(season)
    {
        case spring:
        {

            printf("spring");
            break;        }
        case summer:

        {
            printf("summer");
            break;
        }
        case autumn:
        {
            printf("autumn");
            break;

        }
            case winter:
        {
            printf("winter");
            break;
        }
            default:
        {
            printf("未知");
        }

}
}

ios学习Day3xiawu