/in/foo.cc:1:1: error: expected unqualified-id before 'if'
 if(y%4==0&&y%100!=0||y%400==0)
 ^~
/in/foo.cc:3:2: error: expected unqualified-id before 'else'
  else
  ^~~~
/in/foo.cc:5:2: error: expected unqualified-id before 'if'
  if(m==2)
  ^~
/in/foo.cc:7:2: error: expected unqualified-id before 'else'
  else
  ^~~~