List内部结构完全不同于array, vector, deque。
它提供了两个pointer,指向第一个和最后一个元素。
不支持随机访问元素,因此要访问第n个元素必须爬过n - 1个元素。
在任何位置上执行元素的插入和删除操作都很快。
因此会有一些属于list的特殊类型操作,比如merge, splice等。
ListTest.cpp
#include <iostream> #include <deque> #include <list> #include <iostream> #include <algorithm> #include <iterator> #include "ListTest.h" using namespace std; void ListTest::printLists(const list<int>& l1, const list<int>& l2) { cout << "list1: "; copy(l1.cbegin(), l1.cend(), ostream_iterator<int>(cout, " ")); cout << endl << "list2: "; copy(l2.cbegin(), l2.cend(), ostream_iterator<int>(cout, " ")); cout << endl << endl; } void ListTest::simpleOperation() { // create two empty lists list<int> list1, list2; // fill both lists with elements for (int i = 0; i<6; ++i) { list1.push_back(i); list2.push_front(i); } printLists(list1, list2); // insert all elements of list1 before the first element with value 3 of list2 // - find() returns an iterator to the first element with value 3 list2.splice(find(list2.begin(), list2.end(), // destination position 3), list1); // source list printLists(list1, list2); // move first element of list2 to the end list2.splice(list2.end(), // destination position list2, // source list list2.begin()); // source position printLists(list1, list2); // sort second list, assign to list1 and remove duplicates list2.sort(); list1 = list2; list2.unique(); printLists(list1, list2); // merge both sorted lists into the first list list1.merge(list2); printLists(list1, list2); // remove all even elements list1.remove_if([](int i) { return i % 2 == 0; }); printLists(list1, list2); } void ListTest::run() { printStart("simpleOperation()"); simpleOperation(); printEnd("simpleOperation()"); }
运行结果:
---------------- simpleOperation(): Run Start ----------------
list1: 0 1 2 3 4 5
list2: 5 4 3 2 1 0
list1:
list2: 5 4 0 1 2 3 4 5 3 2 1 0
list1:
list2: 4 0 1 2 3 4 5 3 2 1 0 5
list1: 0 0 1 1 2 2 3 3 4 4 5 5
list2: 0 1 2 3 4 5
list1: 0 0 0 1 1 1 2 2 2 3 3 3 4 4 4 5 5 5
list2:
list1: 1 1 1 3 3 3 5 5 5
list2:
---------------- simpleOperation(): Run End ----------------