Roeloff, Is this for the Advent of Code 2018? The easiest way is to read the input file... Then, I can guide you from there! ;) ----------------- Benoît St-Jean Yahoo! Messenger: bstjean Twitter: @BenLeChialeux Pinterest: benoitstjean Instagram: Chef_Benito IRC: lamneth Blogue: endormitoire.wordpress.com "A standpoint is an intellectual horizon of radius zero". (A. Einstein) On Sunday, December 2, 2018, 4:49:06 a.m. EST, Roelof Wobben <r.wobben@home.nl> wrote: Hello, I have a collection that looks like this : sampleData1    "comment stating purpose of message"    ^ #( -8    +7) I want to add those numbers up but the code chokes at the + so I did this : FrequencyFinderData new class sampleData1  inject: 0 into: [:sum :each | (each ~= $+) ifTrue: [sum + each asInteger] ] so when the each is not a + it must count it but still the code chokes at the + Where do I think wrong ? Roelof