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procedure main ()
   write ("Hello, world!")
end

procedure main ()
   local i, j
   every write (i := 1 to 20, "! = ", { j := 1; every j *:= 1 to i; j })
end

procedure factorial (n)
   if n = 0 then
      return 1
   else if n >= 0 then
      return n * factorial (n - 1)
end

procedure main ()
   local i
   every i := 1 to 20 do
      write (i, "! = ", factorial (i))
end

global fib_memo

procedure fib (n)
   if n >= 0 then
      return ((/fib_memo [n] := fib (n - 2) + fib (n - 1)) | fib_memo [n])
end

procedure main ()
   local first, i
   fib_memo := table ()
   fib_memo [0] := 0; fib_memo [1] := 1
   every i := 1 to 20 do {
      if \first then writes (", ")
      writes (fib (i))
      first := 1
   }
end