method f1(a b) return a - (b * -1); end; method f2(a b) return a - (b * -2); end; method f4(a b) return a - (b * -4); end; method f8(a b) return a - (b * -8); end; method f(a b c d) return a - ((b - ((c - (d * -2)) * -4)) * -8); end;