/in/foo.c: In function 'main':
/in/foo.c:6:6: warning: 'year' is used uninitialized in this function [-Wuninitialized]
  int r4=year%4;
      ^~
/in/foo.c:19:10: warning: 'month' is used uninitialized in this function [-Wuninitialized]
  if(month==4|| month==6 ||month==9 ||month==11)
     ~~~~~^~~