What language cavemen could program in?

C/C++ syntax is quite unforgiving for mistakes, and cavemen weren't good abstract thinkers.
I think something like a variant of LISP or Forth could be used to teach a cavemen basic programming.
Haskell or restricted subset of it, would look like pseudocode and could be more palatable to primitive cavemen

Pascal. I had a discrete math professor once who fucking loved Pascal. He was some kind of kike from eastern Europe. His face was mishappen and bubbly and he had a huge jew nose and and his hair grew in patches and he went off in tangents about Godel like some sort of crazed monkey-man. He looked like a stereotypical disgusting subhuman caveman Homo Erectus who had been dug out of some million year old burial site, shipped to the anthropology school for study, but had come back to life and wondered over to the mathematics college. The bastard had the nerve to offer me an undergraduate research job and write me a letter of recommendation for grad school. Absolute savage.