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    1  MODULE PVarPar;
    2  VAR a, b : INTEGER; ExitCode : INTEGER;
    3  PROCEDURE Swap(VAR x, y : INTEGER);
    4  VAR t : INTEGER;
    5  BEGIN
    6    t := x; x := y; y := t
    7  END Swap;
    8  BEGIN
    9    a := 12; b := 30;
   10    Swap(a, b);
   11    ExitCode := a * 100 + b
   12  END PVarPar.

    0 errors