As I promised, this is the first SFP ______________________________________________________________ In a remote island, the language used by the locals only uses seven letters: A, B, C, D, E, F, G. We say that two words are synonymous if we can transform one into the other according to the following rules: Rule 1. You may change a letter into two letters in the following way: A --> BC, B --> CD, C --> DE, D --> EF, E --> FG, F --> GA, G --> AB. Rule 2. If a letter is between two equal letters, the two equal letters can be removed. For example, DFD --> F. For example, BED is synonymous with BEEF by Rule 1; BABE is synonymous with AE by Rule 2. Show that all words in this language are synonymous. ____________________________________________________________________ Good luck~