foo.c:1:1: error: unknown type name 'INPUTn'
    1 | INPUTn
      | ^~~~~~
foo.c:2:3: error: 'nMOD3' undeclared here (not in a function)
    2 | a=nMOD3
      |   ^~~~~
foo.c:3:1: error: expected ',' or ';' before 'b'
    3 | b=nMOD4
      | ^

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