链表（c++版本)

由于自己已经转到c++了，所以想要用c++实现数据结构，具体大概包括链表，栈，队列，图，树，查找等方面的内容，并尽力去造个轮子

#include
#include
using namespace std;
//数据结构
struct ListNode {//链节点
	int val;
	ListNode* next;
	ListNode() :val(0), next(nullptr) {};
	ListNode(int x) :val(x), next(nullptr) {};
	ListNode(int x, ListNode* next) :val(x), next(next) {};
};
ListNode* head = new ListNode(-1);//头节点
bool deleteNode(int val) {//链表的删除
	ListNode* pre = head;
	ListNode* curr = head->next;
	while (curr) {
		if (curr->val == val) {
			ListNode* temp = curr;
			pre->next = curr->next;
			delete temp;
			return true;
		}
		pre = pre->next;
		curr = curr->next;
	}
	return false;
}
bool insertNode(int val) {//链表的加入
	ListNode* tail = head->next;
	head->next = new ListNode(val);
	head->next->next = tail;
	return true;
}
void traverse() {
	ListNode* curr = head->next;
	if (curr == nullptr)cout << "没有元素" << endl;
	while (curr) {
		cout << curr->val << " ";
		curr = curr->next;
	}
	cout << endl;
}
int main() {
	cout << "按1加入元素" << endl << "按2删除元素" << endl << "按3遍历元素" << "按其他键退出" << endl;
	while (1) {
		int control;
		cout << "请输入(1 - 3)来进行操作:" << endl;
		//cout << endl;
		cin >> control;
		int val;
		bool ret = false;
		switch (control) {
		case 1:
			cout << "请输入要加入的元素:" << endl;
			cin >> val;
			ret=insertNode(val);
			if (!ret)cout << "插入元素有问题" << endl;
			break;
		case 2:
			cout << "请输入要删除的元素：" << endl;
			cin >> val;
			 ret=deleteNode(val);
			if (!ret)cout << "没有要删除的元素" << endl;
			break;
		case 3:
			cout << "经过遍历可以得到：" << endl;
			traverse();
			break;
		default:
			exit(0);
			break;
		}
	}
	return 0;
}