Functional Programming, Haskell, Computer Science, Lambda Calculus, Algorithms.
c = λm.λn.λo.(n λp.λq.(p (λr.a m))) a ---------------- a = (((b c) d) & ((e c) d)) e = λf.λg.(f λh.λi.(h λj.λk.k)) d = λl.λm.m c = λn.λo.λp.(o λq.λr.(q (λs.a n))) a ---------------- c = λd.λe.e b = λf.λg.λh.(g λi.λj.(i (λk.((k b) c) f))) a = λl.λm.(l λn.λo.(n λp.λq.q)) ((a b) c) ---------------- d