PROGRAM main
  FUNCTION foo(x, y : INTEGER): INTEGER;
    VAR
      i, j, k : INTEGER;
    ENDVAR
    BEGIN
    k := 1;
    j := 0;
    WHILE k <> y - 1 DO
    BEGIN
      k := (k * x) mod y;
      j := j + 1;
    END
    foo := j;
    END
  
  BEGIN
    VAR %% can be empty or completely missing
    ENDVAR
    BEGIN
      VAR
        w, x, z: INTEGER;
      ENDVAR
      x := foo(7, 97);
      WRITE(x);
      WRITESP();
      z := foo(13, 17);
      WRITE(z);
      WRITELN();
    END
  END