Abstract: This paper introduces the related content list container.
1, the basic concept
1.1 brief list of
List storage unit is a physically non-contiguous, non-sequential storage structure, the logical order of the data elements is achieved by the link pointer in the linked list order. Chain by a series of nodes (each node element is called a linked list), with the node can be dynamically generated at runtime. Each node consists of two parts: a data field storing data elements, and the other is stored under a node address pointer field.
Compared to continuous linear space of vector, list becomes many complex and its benefits is that each insert or delete an element, or free up space is to configure an element. Therefore, list the use of space for absolutely accurate, is not wasted. Also, for any position of insertion of the element or elements to remove, list all be done.
1.2 features list
- Dynamic storage allocation, will not cause waste and overflow memory
- List insertion and deletion operation is very convenient, you can modify the pointer without moving the large number of elements
- Flexible list, but space and time-consuming extra large
2, list the container iterator
List container not like as an ordinary vector pointers as iterators, since it can not be guaranteed in a node with a continuous memory space. List iterator must have the ability to point list of nodes, and the ability to correct increasing, decreasing, value, member of the access operation. Take-called "list right increment, decrement, value, access to the members" refers, incremented point to the next node, a node point on decreasing, the value is taken when the data value of the node, when the access member is member nodes.
Since the list is a doubly linked list, iterators must be able to have the forward, backward capability, so the container list is provided Bidirectional Iterators.
List has an important property, insert and delete operations will not cause failure of the original list iterator. This is not true in the vector, because the vector insertion operation may cause memory weight the new configuration, resulting in the original iterators all fail, or even delete elements of the List, only iterators are deleted that element fails, the other iterator does not affected in any way.
3, commonly used API
| API | significance | |
| Constructor | list<T> lstT | Using a template class that implements the use of default constructor form of an object |
| list(beg,end) |
Constructor [beg, end] to copy an element interval itself | |
| list(n,elem) | The constructor for the n copies itself elem | |
| list(const list &lst) | Copy constructor | |
| Data elements insert and delete operations | push_back(elem) | Add an element to the end of the container |
| pop_back() | The last element to delete container | |
| push_front (element) | Insert an element at the beginning of the container | |
| pop_front() | Removes the first element from the beginning of the container | |
| insert(pos,elem) | Elem copy insertion element in the position pos, the new data location | |
| insert(pos,n,elem) | Inserts n elem data position pos, no return value | |
| insert(pos,beg,end) | Insert [BEG, the data end) section at the position pos, no return value | |
| clear() | All data removed containers | |
| erase(beg,end) | Erasure position [BEG, the data end) section, the next data return | |
| erase(pos) | Delete data position pos Returns the location of the next data | |
| remove(elem) | Delete all the elements in the container matches the value of elem | |
| The size of the operation | size() |
Returns the number of elements of the container |
| empty() | Determining whether the container is empty | |
| resize(num) | The length of the container is re-designated num, if the container becomes long, filled in a default value of the new position. If the container becomes short, the elements of the container beyond the end of the length of the deleted |
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| resize(num, elem) | The length of the container is re-designated num, if the container becomes longer, the value to fill the new position places elem. If the container becomes short, the elements of the container beyond the end of the length of the deleted |
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| Assignment | assign(beg, end); | The [beg, end) copy of the data interval is assigned to itself |
| assign(n, elem) | The n copies assigned to itself elem | |
| list& operator=(const list &lst) | Equality operator overloading | |
| swap(lst) | The lst element itself interchangeable with | |
| Data Access | front() | Returns the first element |
| back() | Returns the last element | |
| Reverse the sort | reverse() | 反转链表，比如lst包含1,3,5元素，运行此方法后，lst就包含5,3,1元素 |
| sort() | list排序 |
4、代码示例
1 #define _CRT_SECURE_NO_WARNINGS 2 #include<iostream> 3 #include<list> 4 #include <algorithm> 5 #include <string> 6 7 using namespace std; 8 9 void printList(list<int>&L) { 10 for (list<int>::iterator it = L.begin(); it != L.end();it++) { 11 cout << *it << " "; 12 } 13 cout << endl; 14 } 15 16 void test01() { //初始化，打印 17 list<int>L1(10,10); 18 list<int>L2(L1.begin(),L1.end()); 19 printList(L1); 20 printList(L2); 21 L2.push_back(100); 22 printList(L2); 23 24 //逆序打印 25 for (list<int>::reverse_iterator it=L2.rbegin();it!=L2.rend();it++) 26 { 27 cout << *it <<" "; 28 } 29 cout << endl; 30 31 list<int>L3; //首尾插入元素 32 L3.push_back(10); 33 L3.push_back(20); 34 L3.push_back(30); 35 L3.push_front(100); 36 L3.push_front(200); 37 L3.push_front(300); 38 39 printList(L3); 40 L3.pop_front(); //删除头部和尾部 41 L3.pop_back(); 42 printList(L3); 43 44 L3.insert(L3.begin(), 1000); //指定位置插入 45 printList(L3); 46 47 L3.remove(10); //去除10这个元素 48 printList(L3); 49 } 50 51 void test02() { //容量大小的改变 52 list<int>L4; 53 L4.push_back(10); 54 L4.push_back(20); 55 L4.push_back(30); 56 L4.push_front(100); 57 L4.push_front(200); 58 L4.push_front(300); 59 cout << L4.size() << endl; //输出大小 60 if (L4.empty()) 61 { 62 cout << "链表为空" << endl; 63 } 64 else { 65 cout << "链表不为空" << endl; 66 } 67 68 L4.resize(10); //扩充补0 69 printList(L4); 70 71 L4.resize(3); //只留3个 72 printList(L4); 73 74 list<int>L5; 75 L5.assign(L4.begin(), L4.end()); 76 printList(L5); 77 78 cout << L5.front() << endl; 79 cout << L5.back() << endl; 80 } 81 82 bool mycompare(int v1,int v2) { 83 return v1 > v2; 84 } 85 86 void test03() { //反转、排序 87 list<int>L; 88 L.push_back(10); 89 L.push_back(50); 90 L.push_back(20); 91 L.push_back(60); 92 93 L.reverse(); //进行了反转 94 printList(L); 95 96 L.sort(); //进行了从小到大的排列 97 printList(L); 98 99 L.sort(mycompare); //进行了从大到小的排列 100 printList(L); 101 } 102 103 class Person { 104 public: 105 string m_name; 106 int m_age; 107 int m_height; 108 Person(string name,int age,int height):m_name(name),m_age(age),m_height(height) {} 109 110 //重载 == 让remove 可以删除自定义的person类型 111 bool operator==(const Person & p) 112 { 113 if (this->m_name == p.m_name && this->m_age == p.m_age && this->m_height == p.m_height) 114 { 115 return true; 116 } 117 return false; 118 } 119 }; 120 121 bool mycompareperson(Person &p1,Person &p2) { 122 if (p1.m_age==p2.m_age) 123 { 124 return p1.m_height < p2.m_height; 125 } 126 else { 127 return p1.m_age > p2.m_age; 128 } 129 } 130 131 void test04(){ 132 list<Person>L; 133 Person p1("火男",20,165); 134 Person p2("亚瑟", 26, 170); 135 Person p3("诸葛亮", 29, 175); 136 Person p4("周瑜", 26, 176); 137 Person p5("李典", 35, 180); 138 Person p6("不知火舞", 19, 172); 139 Person p7("后羿", 39, 188); 140 141 L.push_back(p1); 142 L.push_back(p2); 143 L.push_back(p3); 144 L.push_back(p4); 145 L.push_back(p5); 146 L.push_back(p6); 147 L.push_back(p7); 148 149 L.sort(mycompareperson); 150 for (list<Person>::iterator it=L.begin();it!=L.end();it++) 151 { 152 cout << "姓名: "<< it->m_name <<"年龄： "<<(*it).m_age<<"身高： "<<it->m_height<< endl; 153 } 154 155 L.remove(p6); 156 for (list<Person>::iterator it = L.begin(); it != L.end(); it++) 157 { 158 cout << "姓名: " << it->m_name << "年龄： " << (*it).m_age << "身高： " << it->m_height << endl; 159 } 160 } 161 162 int main() { 163 //test01(); 164 //test02(); 165 //test03(); 166 test04(); 167 system("pause"); 168 return 0; 169 }