/in/foo.cc:1:1: error: 'input' does not name a type; did you mean 'int'?
    1 | input = STDIN.read.split
      | ^~~~~
      | int
/in/foo.cc:13:3: error: expected unqualified-id before 'if'
   13 |   if idx && n_strings[idx].start_with?(ms)
      |   ^~