标准STL中list的各个接口的使用

Myth丶恋晨 2022-06-17 08:14 151阅读 0赞

list是标准STL的序列式容器,它里面的元素是有序的线性序列  
STL中的list就是一个带头结点的循环双向链表，可以高效的删除和插入元素。  
但是list是不支持随机访问的，因为它的存储空间是不连续的。  
而且标准的STL的list我们是通过迭代器来遍历容器里的元素的，迭代器是一种检查容器内元素并遍历元素的数据类型。  
标准STL中list的成员函数  
![这里写图片描述][SouthEast]

constructor:list的成员函数  
1、explicit list ( const Allocator& = Allocator() );  
默认的构造函数这个链表的是空的。  
2、explicit list ( size\_type n, const T& value = T(), const Allocator& = Allocator() );  
带参数的构造函数，构造有n个值为value结点  
3、template < class InputIterator >  
list ( InputIterator first, InputIterator last, const Allocator& = Allocator() );  
构造函数的参数类型为迭代器的类型  
4、list ( const list

#include<iostream>
    #include<list>
    using namespace std;
    void FunTest()
    {
        list<int>first;
        //使用默认的构造函数创造first这个对象，但是这个对象里面的内容是空的
    
        list<int>second(4, 100);
        //使用带参数的构造函数去创建4个值为100的结点的对象
    
        list<int>third(second.begin(), second.end());
        //使用带迭代器参数的构造函数将一段区间的内容复制过来
    
        list<int>forth(third);
        //拷贝构造函数
    
        list<int>::iterator it1;//使用迭代器去遍历first对象里的元素
        list<int>::iterator it2;//使用迭代器去遍历second对象里的元素
        list<int>::iterator it3;//使用迭代器去遍历third对象里的元素
        list<int>::iterator it4;//使用迭代器去遍历forth对象里的元素
        it1 = first.begin();
        while (it1 != first.end())
        {
            cout << *it1 << " ";
            ++it1;
        }
        cout << endl;
    
        it2 = second.begin();
        while (it2 != second.end())
        {
            cout << *it2 << " ";
            ++it2;
        }
        cout << endl;
    
        it3 = third.begin();
        while (it3 != third.end())
        {
            cout << *it3 << " ";
            ++it3;
        }
        cout << endl;
    
        it4 = forth.begin();
        while (it4 != forth.end())
        {
            cout << *it4 << " ";
            ++it4;
        }
        cout << endl;
    }

![这里写图片描述][SouthEast 1]

**2、destructor关于析构函数的使用：**  
~list ( );  
它是用来回收我们之前分配的内存，当然STL中的内存分配是由它自己的空间配置器来分配内存的

**3、operator=对运算符’=’的重载**

void FunTest2()
    {
        list<int> first(5, 10);
        list<int> second(3, 1);
        list<int>::iterator it2;
        it2 = second.begin();
        while (it2 != second.end())
        {
            cout << *it2 << " ";
            ++it2;
        }
        cout << endl;
        list<int>::iterator it1;
        second = first;
         it1= second.begin();
        while (it1 != second.end())
        {
            cout << *it1 << " ";
            ++it1;
        }
        cout << endl;
    }

**4、迭代器的使用**  
1>begin()  
iterator begin ();  
const\_iterator begin () const;  
2>end();  
iterator end ();  
const\_iterator end () const;

void FunTest3()
    {
        list<int> l(10,100);
        list<int>::iterator it1=l.begin();//l.begin返回的是非const类型的迭代器是可以修改的
        while (it1 != l.end())
        {
            *it1=10;//迭代器里的解引用这个操作符是重载过的表示迭代器里结点里的data的值
            cout << *it1 << " ";
            ++it1;
        }
        cout << endl;
    }

void FunTest4()
    {
        list<int>l(10, 2);
        list<int>::const_iterator it = l.begin();
        while (it != l.end())
        {
            //*it = 10;//是不能赋值的因为const修饰的迭代器表示这里面的内容是不可以修改的
            cout << *it << " ";
            ++it;
        }//以上的迭代器都是正向遍历容器里的元素的
    }

3>rbegin():  
reverse\_iterator rbegin();  
const\_reverse\_iterator rbegin() const;  
3>rend():  
reverse\_iterator rend();  
const\_reverse\_iterator rend() const;

void FunTest5()
    {
        list<int>l;
        l.push_back(1);
        l.push_back(2);
        l.push_back(3);
        l.push_back(4);
        list<int>::reverse_iterator it = l.rbegin();
        while (it != l.rend())
        {
            cout << *it << " ";
            ++it;
        }
    }//打印出来的结果是4，3，2，1，因为这个迭代器是反向遍历的，它的头相当于正向迭代器的尾

**5、Capacity:关于容量的一些方法**  
empty();  
bool empty ( ) const;  
size()  
size\_type size() const();

max\_size():  
size\_type max\_size () const;

resize()://具有增容和裁剪的作用  
void resize ( size\_type sz, T c = T() );

void FunTest6()
    {
        list<int>l(10);
        cout << l.empty()<<endl;//判断链表空不空
        cout << l.size()<<endl;//结点的个数
        cout << l.max_size()<<endl;
        l.resize(5);//相当于裁减让链表只剩下5个结点
        cout << l.size() << endl;
        l.resize(10, 8);//将链表变成10个值为8的结点
        cout << l.size() << endl;
    }

front():  
reference front ( );  
const\_reference front ( ) const;  
back();  
reference back ( );  
const\_reference back ( ) const;

void FunTest7()
    {
        list<int>l(10, 2);
        l.push_back(8);
        cout << l.front()<<endl;
        cout << l.back();
    }//front和back是以引用值的方式返回的

**5、Modifiers:关于修改链表的 内容**  
1>assign():  
template  
void assign ( InputIterator first, InputIterator last );//参数直接给成迭代器类型的，赋值的是一段区间  
void assign ( size\_type n, const T& u );//直接赋值给链表值为u的结点

void FunTest8()
    {
        list<int>first;
        list<int>second(10,20);
        first.assign(7, 10);
        cout << first.size()<<endl;
        list<int>::iterator it1;
        it1 = first.begin();
        while (it1 != first.end())
        {
            cout << *it1 << " ";
            ++it1;
        }
        cout << endl;
        first.assign(second.begin(), second.end());
        list<int>::iterator it2;
        it2 = first.begin();
        while (it2 != first.end())
        {
            cout << *it2 << " ";
            ++it2;
        }
        cout << endl;
        cout << first.size();
    }//list中assign的使用

2>push\_front():  
void push\_front ( const T& x );  
3>push\_back():  
void push\_back ( const T& x );  
4>pop\_front():  
void pop\_front ( )  
5>pop\_back():  
void pop\_back ( );

void FunTest9()
    {
        list<int> l;
        l.push_back(1);
        l.push_back(2);
        l.push_back(3);
        l.push_back(4);
        l.push_back(5);
        l.pop_back();
        l.pop_back();
        l.push_front(7);
        l.push_front(8);
        l.push_front(9);
        l.pop_front();
        l.pop_front();
        list<int>::iterator it2;
        it2 = l.begin();
        while (it2 != l.end())
        {
            cout << *it2 << " ";
            ++it2;
        }
        cout << endl;
    }//list中push_back的用法,pop_back,push_front,pop_front的用法

6>insert():  
iterator insert ( iterator position, const T& x );  
void insert ( iterator position, size\_type n, const T& x );  
template  
void insert ( iterator position, InputIterator first, InputIterator last );

void FunTest10()
    {
        list<int>first;
        list<int>second;
        list<int>third;
        //iterator insert ( iterator position, const T& x );
        first.insert(first.begin(), 8);
    
        //void insert(iterator position, size_type n, const T& x);
        second.insert(second.begin(), 4, 9);
    
        //void insert ( iterator position, InputIterator first, InputIterator last );
        third.insert(third.begin(), second.begin(), second.end());
    
        list<int>::iterator it2;
        it2 = first.begin();
        while (it2 != first.end())
        {
            cout << *it2 << " ";
            ++it2;
        }
        cout << endl;
        list<int>::iterator it3;
        it3 = second.begin();
        while (it3 != second.end())
        {
            cout << *it3 << " ";
            ++it3;
        }
        cout << endl;
        list<int>::iterator it4;
        it4= second.begin();
        while (it4 != second.end())
        {
            cout << *it4 << " ";
            ++it4;
        }
        cout << endl;
    }//list中insert的用法

7>erase():  
iterator erase ( iterator position );  
iterator erase ( iterator first, iterator last );

void FunTest11()
    {
        list<int>l(10, 2);
        //iterator erase(iterator position);
        l.erase(l.begin());
        cout << l.size()<<endl;
        //iterator erase(iterator first, iterator last);
        l.erase(l.begin(), l.end());
        cout << l.size()<<endl;
    }//erase的用法

8>swap():  
void swap ( list

void FunTest12()
    {
        list<int>l1(10, 2);
        list<int>l2(10, 3);
        l2.swap(l1);
        list<int>::iterator it4;
        it4 = l1.begin();
        cout << "l1:";
        while (it4 !=l1.end())
        {
            cout << *it4 << " ";
            ++it4;
        }
        cout << endl;
        cout << "12:";
        list<int>::iterator it5=l2.begin();
        while (it5 != l2.end())
        {
            cout << *it5 << " ";
            ++it5;
        }
    }//list中swap的用法将两个链表的内容交换

9>clear():  
void clear ( );list中clear的用法，清除所有元素

void FunTest13()
    {
        list<int>l(10,5);
        cout<<l.size()<<endl;
        l.clear();
        cout << l.size();
    }//list中clear的用法，清除所有元素

**6、Operations:**  
1>splice():  
void splice ( iterator position, list

void FunTest14()
    {
        //void splice(iterator position, list<T, Allocator>& x);
        list<int>l1(10, 12);
        list<int>l2(10, 13);
        l1.splice(l1.begin(), l2);//把l1的元素从头全部搬移到l2中
        list<int>::iterator it5 = l2.begin();
        while (it5 != l2.end())
        {
            cout << *it5 << " ";
            ++it5;
        }
        cout << endl;
        list<int>::iterator it6 = l1.begin();
        while (it6 != l1.end())
        {
            cout << *it6 << " ";
            ++it6;
        }
        cout << endl;
        //void splice(iterator position, list<T, Allocator>& x, iterator i);
        list<int>l3(10, 1);
        list<int>l4(10, 2);
        list<int>::iterator it7 = l4.begin();
        ++it7;
        l3.splice(l3.begin(), l4,it7);
        list<int>::iterator it8 = l4.begin();
        while (it8 != l4.end())
        {
            cout << *it8 << " ";
            ++it8;
        }
        cout << endl;
        list<int>::iterator it9 = l3.begin();
        while (it9 != l3.end())
        {
            cout << *it9 << " ";
            ++it9;
        }
        cout << endl;
        //void splice(iterator position, list<T, Allocator>& x, iterator first, iterator last);
        list<int>l5(10, 100);
        list<int>l6(10, 200);
        l5.splice(l5.begin(), l6, ++l6.begin(), l6.end());//把l6从++l6.begin()到l6.end()个元素全部搬移到l5中
        list<int>::iterator it10 = l5.begin();
        while (it10 != l5.end())
        {
            cout << *it10<<" ";
            it10++;
        }
        cout << endl;
    }//list中splice的用法

2>remove():  
void remove ( const T& value );

void FunTest15()
    {
        list<int>l1(10, 8);
        l1.remove(8);//移除l1中所有值为8的结点
        cout << l1.size();
    }//list中remove的用法

3>remove\_if():  
template  
void remove\_if ( Predicate pred );//对这个用法还不太了解

4>unique():  
void unique ( );//删除重复的元素只保留一份  
template  
void unique ( BinaryPredicate binary\_pred );

void FunTest16()
    {
        /*void unique(); template <class BinaryPredicate> void unique(BinaryPredicate binary_pred);*/
        list<int>l1(10, 100);
        l1.unique();//只保留一份，移除重复元素
        cout << l1.size();
    }

5>merge():  
void merge ( list

void FunTest17()
    {
        //void merge(list<T, Allocator>& x);
        list<int>l1(10, 1);
        list<int>l2(10, 2);
        l1.merge(l2);//把l2中所有的元素都合并到l1中
        list<int>::iterator it10 = l1.begin();
        while (it10 != l1.end())
        {
            cout << *it10 << " ";
            it10++;
        }
        cout << endl;
        /*template <class Compare> void merge(list<T, Allocator>& x, Compare comp);*/
    }

6>sort()://对链表的的无序元素进行排序  
void sort ( );  
template  
void sort ( Compare comp );//涉及到仿函数的使用决定是升序排列还是降序排列

void FunTest18()
    {
        list<int>l;
        l.push_back(3);
        l.push_back(1);
        l.push_back(4);
        l.sort();
        list<int>::iterator it1 = l.begin();
        while (it1 != l.end())
        {
            cout << *it1 << " ";
            ++it1;
        }   
    }

[SouthEast]: /images/20220617/c0e9a289b4ce433e8fd97ac87109624a.png
[SouthEast 1]: /images/20220617/dd738449959648578a2de2c8acd847e9.png