foo.c: In function 'main':
foo.c:6:29: error: 'month\U0000ff09\U0000ff1b' undeclared (first use in this function)
    6 |         scanf("%d%d",&year,&month）；
      |                             ^~~~~~~~~
foo.c:6:29: note: each undeclared identifier is reported only once for each function it appears in
foo.c:6:38: error: expected ')' before 'switch'
    6 |         scanf("%d%d",&year,&month）；
      |              ~                       ^
      |                                      )
    7 |                   switch(month){
      |                   ~~~~~~              
foo.c:25:28: error: expected ';' before '}' token
   25 |                   return 0;
      |                            ^
      |                            ;
   26 |                   }
      |                   ~         
foo.c:5:16: warning: unused variable 'days' [-Wunused-variable]
    5 | int year,month,days;
      |                ^~~~
foo.c:5:10: warning: unused variable 'month' [-Wunused-variable]
    5 | int year,month,days;
      |          ^~~~~
foo.c: At top level:
foo.c:29:1: error: expected identifier or '(' before '}' token
   29 | }
      | ^

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