RLE drill

# RLE basic

function main(x::String)
    n = length(x) # number of characters in input
    y = Array{Tuple}(undef, n) # output array
    tc = 0 # touple counter semaphore
    c = 1 # another counter semaphore
    last_character = x[1] # the character to register in the output array

    for i = 2:n
        new_character = x[i]

        if new_character == last_character
            c += 1
        else
            tc += 1
            y[tc] = (last_character, c)
            c = 1
            last_character = new_character
        end
    end

    tc += 1
    y[tc] = (last_character, c)
    return y[1:tc]
end