（一）了解list
list是一个十分强大的链表容器概念！
可以进行各种遍历、插入、删除、去重、合并、拼接、排序等。

（二）Test_Demo

#include <iostream>
#include <list>//链表结构

using namespace std;

int main()
{
	/***************Demo1 list definee*************************/
	list<int> lint0;
	list<int> lint1{ 1, 2, 3 };
	list<int> lint2(lint1);
	list<int> lint3 = lint1;
	list<int> lint4 = {1, 0, 9, 8};

	/***************Demo list options*****************************/
	//正反向迭代遍历list
	for (auto it : lint1) {
		cout << it << " ";
	}
	cout << endl;
	//正向迭代
	for (list<int>::iterator it = lint1.begin(); it != lint1.end(); ++it) {
		cout << *it << " ";
	}
	cout << endl;
	//反向迭代
	for (auto it = lint1.rbegin(); it != lint1.rend(); ++it) {
		cout << *it << " ";
	}
	cout << endl;
	//const正向迭代
	for (auto it = lint1.cbegin(); it != lint1.cend(); ++it) {
		cout << *it << " ";
	}
	cout << endl;

	//在list的头尾插入 一个 数据
	lint1.push_back(9);
	lint1.push_front(10);
	for (auto it : lint1) {
		cout << it << " ";
	}
	lint1.insert(lint1.begin()++, 11); //在list任意位置（迭代器位置参数）插入one数据
	cout << endl;
	//删除数据 与 清空list
	lint1.pop_back();
	lint1.pop_front();
	for (auto it : lint1) {
		cout << it << " ";
	}
	cout << endl;
	lint1.erase(lint1.begin()++);//在list任意位置（迭代器位置参数）删除one数据
	lint1.remove(3);  //删除一个value  = 3
	//remove_if(comp) 删除条件满足的元素,参数为自定义的回调函数
	lint1.clear();
	if (lint1.empty())
		cout << "lint1 is empty!" << endl;
	else
		cout << "lint1.clear() failed!" << endl;

	//size
	for (auto it : lint2) {
		cout << it << " ";
	}
	cout << endl;
	cout << "size = " << lint2.size() << "\tmax_size = " << lint2.max_size() << endl;

	//排序
	lint4.sort();//默认升序
	for (auto it : lint4) {
		cout << it << " ";
	}
	cout << endl;
	//lint4.sort(sortfunc) 自定义条件排序
	
	//mager two list
	lint2.merge(lint4);  //有序（升序）合并，会释放掉lint4
	for (auto it : lint2) {
		cout << it << " ";
	}
	cout << endl;
	if (lint4.empty())
		cout << "lint4 have been free!" << endl;
	//or lint2.merage(lint4, comp);自定义条件合并

	//连接two list
	lint2.splice(lint2.begin(), lint3);//将整个lint3拼接在lint2.begin()， 并free lint3
	//lint2.splice(lint2.begin(), lint3, lint3.begin());//将lint3.begin() 这个元素 拼接在lint2.begin()， 并free lint3.begin()
	//将[lint3.begin(), lint3.end()++] 这段元素 拼接在lint2.begin()， 并free 这个区间的元素
	//lint2.splice(lint2.begin(), lint3, lint3.begin(), lint3.end()++);
	for (auto it : lint2) {
		cout << it << " ";
	}
	cout << endl;
	//反转list
	lint2.reverse();
	for (auto it : lint2) {
		cout << it << " ";
	}
	cout << endl;
	//去重
	lint2.unique();
	for (auto it : lint2) {
		cout << it << " ";
	}
	cout << endl;

	return 0;
}