Home » C++ STL

Assign the elements to the list (different methods) - Example of list::assign() | C++ STL

Example of list::assign() in C++ STL: Here, we are going to learn how to assign the elements, replaces the elements to the list by using list::assign() method in C++ STL?
Submitted by IncludeHelp, on November 01, 2018

list::assign() in C++ STL

It assigns or replaces the elements to the list.

Example to assign the elements to the list

In the given example, there are 3 different methods are used to assign/replace elements to the list.

#include <iostream>
#include <list>
using namespace std;

// function to display the list
void dispList(list<int> L) {
  // declaring interator to the list
  list<int>::iterator l_iter;
  for (l_iter = L.begin(); l_iter != L.end(); l_iter++) cout << *l_iter << " ";
  cout << endl;
}

int main() {
  list<int> list1;
  list<int> list2;
  list<int> list3;
  list<int> list4;

  // assigning 100 to 5 elements
  list1.assign(5, 100);
  cout << "size of list1: " << list1.size() << endl;
  cout << "Elements of list1: ";
  dispList(list1);

  // assigning all elements of list1 to list2
  list2.assign(list1.begin(), list1.end());
  cout << "size of list2: " << list2.size() << endl;
  cout << "Elements of list2: ";
  dispList(list2);

  // assigning list by array elements
  int arr[] = {10, 20, 30, 40};
  list3.assign(arr, arr + 4);
  cout << "size of list3: " << list3.size() << endl;
  cout << "Elements of list3: ";
  dispList(list3);
  return 0;
}

Output

size of list1: 5
Elements of list1: 100 100 100 100 100
size of list2: 5
Elements of list2: 100 100 100 100 100
size of list3: 4
Elements of list3: 10 20 30 40  

Ref: list::assign()