Look-and-say sequence
editable example
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ghul
use IO.Std.write_line
use Ghul.Pipes
look_and_say(seed: string) -> Pipe[string] is
let current mut = seed
do
yield current
let said = System.Text.StringBuilder()
let i mut = 0
while i < current.length do
let digit = current[i]
let run mut = 0
while i < current.length /\ current[i] == digit do
run = run + 1
i = i + 1
od
said.append(run)
said.append(digit)
od
current = said.to_string()
od
si
look_and_say("1") |> take(10) |> each(term => write_line(term))