Question

Highly repetitive data can sometimes be compressed using something called run-length encoding: It is shorter to write "8o" instead of "oooooooo".

Each run is represented by a number n, followed by a single non-space character c. Each run is separated by a single space.

Below is a simple decode function:

def rl_decode(s):

return "".join(map(lambda s: int(s[:-1]) * s[-1], s.split()))

You must write the inverse function

  rl_encode(s)
  

that consumes a space-less string s, and returns its run length encoding.

Examples:

rl_encode("CCCCCCAATTTT") => "6C 2A 4T"
rl_encode("aa") => "2a"

Do not abstract list functions, map, and filter are not allowed. Recursion is also prohibited!

Answer 1

Python code:

# required function

def rl_encode(string):

    #variable for storing output string

    e_str=""

    #Stores count

    count=1

    #looping to create encoded string

    for i in range(1,len(string)):

        #checking if adjacent characters are same

        if(string[i]==string[i-1]):

            #incrementing count

            count+=1

        else:

            #adding to e_str count and the character

            e_str=e_str+str(count)+string[i-1]+" "

            #assigning count as 1

            count=1

    #adding count and final character

    e_str=e_str+str(count)+string[i]

    #returning e_str

    return(e_str)

#checking and printing value returned by rl_encode

print(rl_encode("CCCCCCAATTTT"))

print(rl_encode("aa"))

Screenshot:

Output: