vector emplace() in C++

emplace(): It is a build-in function in STL. It inserts an object in a vector before a specified position. It returns

an iterator that points to the inserted data.

Parameters:

position: It is the constant iterator to the vector.

value: It is the value to be inserted.

Syntax:

vecName.empace(position, value)

Note: This kind of operation are expensive for a vector.

For Example:

vec= {1,2,4,5}

vec.emplace(vec.begin()+2,3) = > vector becomes  {1,2,3,4,5}

Approach

C++

#include <bits/stdc++.h>
using namespace std;

int main()
{
    vector<int> vec = {1, 2, 4, 5};

    auto it = vec.begin();

    it = it + 2;
    vec.emplace(it, 3);

    for (int i = 0; i < vec.size(); i++)
        cout << vec[i] << " ";

    return 0;
}