wf1101/encode_repeating

Encode Repeating

In this assignment, you'll design and implement one of the string manipulation functions that is commonly asked during interviews. Remember that a string is an array of characters. Algorithms that worked on restricted arrays will work on strings as well.

Exercise

• Design and implement a method that updates the string by replacing consecutive repeating characters with a number representing the frequency. The replacement is done only if the string length will get reduced by the process. In addition to .length, you may use .slice! to implement this method.
  • e.g "aaabbbbbcccc" will get replace to "a3b5c4", since a is repeated 3 times, b is repeated 5 times and c is repeated 4 times
  • "xxxyttttgeee" will get replaced with "x3yt4ge3". 'y' and 'g' do not get replaced by "y1" and "g1" since that will increase the length.
  • "ddbbfffgjjjj" will get replaced with "ddbbf3gj4". "dd" and "bb" do not get replaced since the length will remain the same with "d2" and "b2". "g" does not get replaced with "g1" since that will increase the length.
• Share and explain the time and space complexities for your solution.
• At minimum, your implementation should pass the basic tests.

Note: Do not use Ruby provided functionality for .reverse and .reverse!. You may use .length and .slice! to implement this method.

Further reading: Read further on Run-length encoding (RLE), the simple form of loss-less data compression that this assignment is based on.