0 QTRS
lt(0, s(x)) → true lt(x, 0) → false lt(s(x), s(y)) → lt(x, y) fac(x) → help(x, 0) help(x, c) → if(lt(c, x), x, c) if(true, x, c) → times(s(c), help(x, s(c))) if(false, x, c) → s(0)