tests product with three iterables
tests product with three iterables

jkhoogland/cppitertools,tempbottle/cppitertools,ryanhaining/cppitertools,jkhoogland/cppitertools,ryanhaining/cppitertools,jkhoogland/cppitertools,tempbottle/cppitertools,tempbottle/cppitertools,ryanhaining/cppitertools