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Copy a vector to another by using vector.assign() function in C++

C++ STL | Copy one vector to another by using vector.assign() function: Here, we are going to learn how to copy one vector to another by using vector.assign() function?
Submitted by IncludeHelp, on September 27, 2018

Problem statement

Given a vector and we have to assign copy it to another vector by using vector.assign() in C++.

Syntax

Syntax of vector.assign() function:

v2.assign(v1.begin(), v1.end());

C++ program to copy a vector to another by using vector.assign() function

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

int main() {
  // declar and initialize vector 1
  vector<int> v1{10, 20, 30, 40, 50};
  // declare vector2
  vector<int> v2(v1);

  // assign all elements of v1 to v2
  v2.assign(v1.begin(), v1.end());

  // printing v1 and v2
  cout << "v1 elements: ";
  for (int i = 0; i < v1.size(); i++) {
    cout << v1[i] << " ";
  }
  cout << endl;

  cout << "v2 elements: ";
  for (int i = 0; i < v2.size(); i++) {
    cout << v2[i] << " ";
  }
  cout << endl;

  return 0;
}

Output

v1 elements: 10 20 30 40 50
v2 elements: 10 20 30 40 50