list基础用法

1.list的访问就不能用下标+[]了,用迭代器

void test1()
{list<int>lt;//list要带头文件，同理，vector,string也是lt.push_back(1);lt.push_back(2);lt.push_back(3);lt.push_back(4);//list的访问就不能用下标+[]了//用迭代器list<int>::iterator it = lt.begin();while (it != lt.end()){cout << *it;it++;}cout << endl;for (auto e : lt){cout << e;} cout << endl;}

2.emplace_back()几乎是与push_back()用法一致，但也有差别

void test2()
{list<A>lt;A a1(1, 2);lt.push_back(a1);//又名lt.push_back(A(1, 1));//匿名lt.emplace_back(a1);lt.emplace_back(A(1, 1));//差别://push_back()只能传一个参数，emplace_back()支持直接传构造A的对象参数lt.emplace_back(3, 4);}

3.insert(),erase()的用法

void test_list3()
{list<int> lt;lt.push_back(1);lt.push_back(2);lt.push_back(3);lt.push_back(4);lt.push_back(5);lt.push_back(6);//insert()auto it = lt.begin();int k = 3;while (k--){++it;}lt.insert(it, 30);for (auto e : lt){cout << e << " ";}cout << endl;//erase()int x = 0;cin >> x;it = find(lt.begin(), lt.end(), x);if (it != lt.end()){lt.erase(it);}for (auto e : lt){cout << e << " ";}cout << endl;
}

4.reverse()

     lt.reverse();//orreverse(lt.begin(), lt.end());

5.排序

    // 升序lt.sort();//orless<int> ls;lt.sort(ls);//降序greater<int> gt;lt.sort(ls);//orlt.sort(greater<int>());

关于链表排序：链表排序效率非常的低。

6.合并

std::list<double> first, second;first.push_back(3.1);first.push_back(2.2);first.push_back(2.9);second.push_back(3.7);second.push_back(7.1);second.push_back(1.4);first.sort();second.sort();first.merge(second);//second就为空了

7.unique()（去重）

前提：必须保证有序

void test5()
{list<int> lt;lt.push_back(1);lt.push_back(20);lt.push_back(3);lt.push_back(5);lt.push_back(5);lt.push_back(4);lt.push_back(5);lt.push_back(6);lt.sort();for (auto e : lt){cout << e << " ";}cout << endl;lt.unique();for (auto e : lt){cout << e << " ";}cout << endl;
}

8.splice剪切再粘贴

void test6()
{// 一个链表节点转移给另一个链表std::list<int> mylist1, mylist2;std::list<int>::iterator it;// set some initial values:for (int i = 1; i <= 4; ++i)mylist1.push_back(i);      // mylist1: 1 2 3 4for (int i = 1; i <= 3; ++i)mylist2.push_back(i * 10);   // mylist2: 10 20 30it = mylist1.begin();++it;                         // points to 2mylist1.splice(it, mylist2); // mylist1: 1 10 20 30 2 3 4// mylist2 (empty)// "it" still points to 2 (the 5th element
}