sum_elements_in_LL_recursive

sum_elements_in_LL_recursive 问题： class ListNode { constructor(value = 0, next = null) { this.value = value this.next = next } } function sumElements(head) { return -1 } // Test Cases var LL1 = new ListNode(1, new ListNode(4, new ListNode(5))) console.log(sumElements(null)) // 0 console.log(sumElements(LL1)) // 10 console.log(sumElements(new ListNode(1))) // 1