procedure main(A)
    every writes(s := !A, " -> [") do {
        every writes(!(enc := encode(&lcase,s))," ")
        writes("] -> ",s2 := decode(&lcase,enc))
        write((s == s2, " (Correct)") | " (Incorrect)")
        }
end

procedure encode(m,s)
    enc := []
    every c := !s do {
        m ?:= reorder(tab(i := upto(c)),move(1),tab(0))
        put(enc,i-1)   # Strings are 1-based
        }
    return enc
end

procedure decode(m,enc)
    dec := ""
    every i := 1 + !enc do {	# Lists are 1-based
        dec ||:= m[i]
        m ?:= reorder(tab(i),move(1),tab(0))
        }
    return dec
end

procedure reorder(s1,s2,s3)
    return s2||s1||s3
end