What is a List?

A list in STL is a contiguous container that allows the inserting and erasing of elements in constant time and iterating in both directions.

Syntax:

list<object_type> variable_name; 

Example:

list<int> li;
list<string> li;

Functions in List:

• push_back() – to insert an element at the end of the list.

list<int> li;
li.push_back(110);
li.push_back(220);

• push_front() – to insert an element at the front of the list.

list<int> li;
li.push_front(110);
li.push_front(220);

• pop_back() – deletes the last element of the list.

li.pop_back();

• pop_front() – deletes the front element of the list.

li.pop_front();

• front() – it gives a reference to the first element of the list.

li.front();

• back() – it gives a reference to the last element of the list.

li.back();

• reverse() – reverse the list.

li.reverse();

• sort() – sorts the list in ascending order.

li.sort();

• size() – returns the number of elements on the list.

li.size();

• empty() – to check if the list is empty or not.

li.empty();

Code:

#include<bits/stdc++.h>
using namespace std;
void printlist(list<int> li)
{
    list<int>::iterator it;
    for(it=li.begin();it!=li.end();it++)
    {
        cout<<*it<<" ";
    }
    cout<<endl;
}
int main()
{
    list<int> li;
    li.push_back(10);
    li.push_back(20);
    li.push_front(30);
    li.push_front(40);
    li.push_front(50);
    
    cout<<"The elements in the list are: ";
    printlist(li);
    cout<<"Reversing the list: ";
    li.reverse();
    printlist(li);
    cout<<"Sorting the list: ";
    li.sort();
    printlist(li);
    cout<<"The size of the list is: "<<li.size()<<endl;
    cout<<"The first element in the list: "<<li.front()<<endl;
    cout<<"Deleting the first element"<<endl;
    li.pop_front();
    printlist(li);
    cout<<"The last element of the list: "<<li.back()<<endl;
    cout<<"Deleting the last element"<<endl;
    li.pop_back();
    printlist(li);
    
}

Other functions of the list:

• begin() – it refers to the first element of the list.
• end() – it refers to the theoretical element after the last element of the list.
• cbegin() – it refers to the first element of the list.
• cend() – it refers to the theoretical element after the last element of the list.
• rbegin() – it points to the last element of the list.
• rend() – it points to the theoretical element before the first element of the list.
• emplace_front() – to insert an element at the front of the list.
• emplace_back() – to insert an element at the end of the list.
• max_size() – the maximum elements a list can hold.
• clear() – to delete all the elements of the list.
• erase() – to delete a single element or elements between a particular range.

Special thanks to Subhrajit Das for contributing to this article on takeUforward. If you also wish to share your knowledge with the takeUforward fam, please check out this article