Question

Write a function decompressed(count_tuples) that takes a list of counts of '0's and '1's as defined above and returns the expanded (un-compressed) string. You may assume that the first value of count_tuples has a count that is greater than or equal to zero and all other counts are greater than zero.

Comments to show how to figure this out would be greatly appreciated

A data file in which particular characters often occur multiple times in a row can be compressed by a technique called run-length encoding. With this technique a sequence of n occurrences of the character c are represented as the tuple (n. c). For example, the sequence xxxaaaaaqxxxxx would be represented as [(3, 'x'), (5, 'a'), (1, 'q'), (5, 'x')] If we use this technique on a file containing only 'O's and '1's, the tuples will clearly alternate between a count of 'O's and a count of '1's. For example 00111100000011011111 would be encoded as [(2, '0'), (4, '1'), (6, '0'), (2, '1'), (1, '0'), (5, '1')] Since we know that the characters alternate between 'O' and '1', we don't actually need to record them in the encoding and can instead write the above sequence as [2, 4, 6, 2, 1, 5] In this notation, the first number is a count of 'O's, the second is a count of '1's, the third is a count of 'O's, and so on. If the sequence being encoded starts with a '1', the first number in the list will be zero. Write a function decompressed(count_tuples) that takes a list of counts of 'O's and '1's as defined above and returns the expanded (un-compressed) string. You may assume that the first value of count_tuples has a count that is greater than or equal to zero and all other counts are greater than zero. For example: Test Result print(expanded ([2, 4, 6, 2, 1, 5])) 00111100000011011111 print(expanded ([0, 1, 2, 3, 4, 5, 6, 7])) 1001110000111110000001111111 Answer: (penalty regime: 0, 10, 20, ... %)

Answer 1

def decompressed(count_tuples):
    result = ''  # create empty string as result
    for count, char in count_tuples:  # go through each char and it's count from list
        result += char * count  # add the char count number of times to result
    return result  # return the result


# Testing the function here. ignore/remove the code below if not required
print(decompressed([(2, '0'), (4, '1'), (6, '0'), (2, '1'), (1, '0'), (5, '1')]))

00111100000011011111 Process finished with exit code 0