逆置，查找倒数第K个节点，Add函数不用四则运算的实现

//1 逆置单链表，查找倒数第K个节点只遍历一遍#include<iostream>using namespace std;#include<malloc.h>typedef int DataType;struct ListNode{DataType _data;ListNode* _next;ListNode(const DataType& x):_data(x), _next(NULL){}};ListNode* BuyNode(const DataType& x){ListNode* cur = (ListNode*)malloc(sizeof(DataType));cur->_data = x;cur->_next = NULL;return cur;}void Printf(ListNode* list){ListNode* cur = list;if (cur == NULL)return;while (cur){cout << cur->_data << " ";cur = cur->_next;}cout << endl;}void PushFront(ListNode** list, const DataType& x){if (*list == NULL){*list = BuyNode(x);}else{ListNode* next = *list;*list = BuyNode(x);(*list)->_next = next;}}void PushBack(ListNode** list,const DataType& x){ListNode* tail = *list;if (*list == NULL){*list = BuyNode(x);}else{while (tail->_next){tail = tail->_next;}tail->_next = BuyNode(x);}}ListNode* CountBackwards(ListNode* list, int k)//查找倒数第K个节点{if (list == NULL){return NULL;}ListNode* fast = list;ListNode* slow = list;while (--k){fast = fast->_next;}while (fast->_next){slow = slow->_next;fast = fast->_next;}return slow;}void ReverseList(ListNode** list){if (*list == NULL||(*list)->_next==NULL){return;}ListNode* cur = *list;ListNode* tmp = NULL;*list = NULL;while (cur){tmp = cur;cur = cur->_next;PushFront(list, tmp->_data);}}void Test1()   //查找倒数第K个节点{ListNode* list = NULL;PushBack(&list, 2);PushBack(&list, 5);PushBack(&list, 9);PushBack(&list, 8);Printf(list);ListNode* cur=CountBackwards(list, 2);cout << cur->_data << endl;}void Test2()   //逆置单链表{ListNode* list = NULL;PushFront(&list, 2);PushFront(&list, 5);PushFront(&list, 9);PushFront(&list, 8);Printf(list);ReverseList(&list);Printf(list);}int main(){Test2();return 0;}2实现Add函数，不能用四则运算  -->//#include<stdio.h>////int Add(int num1,int  num2)//{//int tmp = 0;//while (num2)//{//tmp = num1^num2;//num2 = (num1&num2) << 1;//num1 = tmp;//}//return num1;//}////int main()//{//int sub = Add(4,5);//printf("%d \n", sub);//return 0;//}