Run-length encoding: Difference between revisions

=={{header|Julia}}==

{{works with|Julia|0.6}}

<lang julia>using IterTools

encode(str::String) = collect((length(g), first(g)) for g in groupby(first, str))

decode(cod::Vector) = join(repeat("$l", n) for (n, l) in cod)

for original in ["aaaaahhhhhhmmmmmmmuiiiiiiiaaaaaa", "WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW"]

encoded = encode(original)

decoded = decode(encoded)

println("Original: $original\n -> encoded: $encoded\n -> decoded: $decoded")

end</lang>

{{out}}

<pre>Original: aaaaahhhhhhmmmmmmmuiiiiiiiaaaaaa

-> encoded: Tuple{Int64,Char}[(5, 'a'), (6, 'h'), (7, 'm'), (1, 'u'), (7, 'i'), (6, 'a')]

-> decoded: aaaaahhhhhhmmmmmmmuiiiiiiiaaaaaa

Original: WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW

-> encoded: Tuple{Int64,Char}[(12, 'W'), (1, 'B'), (12, 'W'), (3, 'B'), (24, 'W'), (1, 'B'), (14, 'W')]

-> decoded: WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW</pre>