This program encodes and decodes secret messages. Simply follow the instructions inside. Qgrf wmivmpb xduilxf pdl lxuilxf fxumxq bxffpvxf. Frbwok nioois qgx rdfqmeuqridf rdfrlx. (5)
Credit to @flun who gave me the idea lxikem mu @vcoy hwu szfi ti mwi ekiz (13) y'c izkiyh pvf tian hvjn igg ltil mvkw zvk jvltyjq