; Using Scheme Given an item, a list of elements, and a non-negative index, ; inserts the item to the list at the index and return ; If the index is too big, returns the same list ; (insert 10 '(1 2 3) 0)--> (10 1 2 3) ; (insert 10 '(1 2 3) 2)--> (1 2 10 3) ; (insert 10 '(1 2 3) 4)--> (1 2 3) (define insert (lambda (item ls idx)