While I'm not a huge fan of functional programming, this can be done pretty easily with a fold. For example in Scala: xs.foldLeft(""){ (prev, cur) => if (pre

While I'm not a huge fan of functional programming, this can be done pretty easily with a fold. For example in Scala: xs.foldLeft(""){ (prev, cur) => if (prev != "a" && cur != "a") parseLine(cur); cur} Although the result is pretty and shorter than your solution, it took me quite a while to figure out how to do it. Also, your code has a bug. You are skipping two lines after every "a". The code should be i += 1 instead of i += 2. <Insert lame joke about mutation causing bugs here.>