c语言作业

#include <stdio.h> 
int main(){ 
  int month, year;
  printf("输入1~12的数字，获取每月的天数:"); 
  scanf("%d", &month);
  
  switch(month){
          case 1: 
          case 3:
          case 5:
          case 7: 
          case 8: 
          case 10:
          case 12: 
                  printf("有31天");
                  break; 
          case 4:
          case 6: 
          case 9:
          case 11:
                  printf("有30天");
                  break;
          case 2: 
                  printf("请输入一个年份："); 
                  scanf("%d", &year); 
                  if((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0)){ 
                  printf("有29天");
                  break; 
                  }else{ 
                  printf("有28天");
                  break;
                  } 
          default: 
                 printf("输入错误"); 
} 
}