allNumLet.forEach(
                    function (el, idx) {
                        console.log(el);
                        console.log(idx);
                        function unEqual(element, index, array) {
                            var a = el;
                            return (element != a);
                        }

                        if (ourNumLet.every(unEqual)) {
                            diff.push(el);
                        }
                    });