#!/usr/bin/ruby func a(k, x1, x2, x3, x4, x5) { k <= 0 ? (x4() + x5()) : func b { a(--k, b, x1, x2, x3, x4) }(); }; assert_eq(a(10, {1}, {-1}, {-1}, {1}, {0}), -67); say "** Test passed!";