新手写c,switch case报错,求解答

Question

原题: 输入年份和月份，输出这一年的这一月有多少天。需要考虑闰年。

#include <stdio.h>

int main()
{
    int year,month;
    scanf("%d %d",&year,&month);
    switch (month)
    case 1:
        printf("31\n");
        break;
    case 2:
        if(year%4==0 && year%100!=0 || year%400==0) 
            printf("29");
        else
            printf("28");
        break;
    case 3:
            printf("31");
            break;
    case 4:
            printf("30");
            break;
    case 5:
            printf("31");
            break;
    case 6:
            printf("30");
            break;
    case 7:
            printf("31");
            break;
    case 8:
            printf("31");
            break;
    case 9:
            printf("30");
            break;
    case 10:
            printf("31");
            break;
    case 11:
            printf("30");
            break;
    default:
            printf("31");
    return 0;
}

编译后报错出现这两玩意
[Error] break statement not within loop or switch
[Error] case label not within a switch statement

Answer 1

switch没加括号