As GePeTo assimilates all data on the internet, they are looking for a way to compress that data so it occupies less space. For this purpose, they came up with the following compression algorithm.

Given a string $$$s$$$ containing lowercase English letters, each maximal consecutive repetition of a letter $$$c$$$ must be replaced by $$$c$$$ followed by $$$n$$$, where $$$n$$$ is the number of repetitions of that letter. If the letter is repeated just once, then it should not be replaced by $$$c1$$$, as that would increase the size of the string.

As an example, consider the string "zzzabbc". Since the letter 'z' is repeated three times consecutively and 'b' twice, the result of the compression is "z3ab2c".

Your task is to implement this algorithm.