String :: Achieve Fast And Effective String Compression

I have an Object which stores pairs for a find and replace that I perform on up to 1500 Strings at a time.The Object is populated with pairs using a method that will accept a String and then store this as a property with the value being an automatically assigned base 36 number, like this:[code]nextShort returns an automatically incremented value being the subject of .toString(36), so running the above a few times might make _pairs look like this:[cod]ehowever in my mind I foresee a massive problem in a case where I might want to "shorten" 2000+ Strings and the _pairs Object has at the same time has over 500 pairs.That ends up being 1,000,000 iterations all up which obviously doesn't seem very efficient at all.