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vector::begin() function with example in C++ STL

C++ STL vector::begin() function: Here, we are going to learn about the begin() function of vector header in C++ STL with example.
Submitted by IncludeHelp, on May 09, 2019

C++ vector::begin() function

vector::begin() is a library function of "vector" header, it is used to get the first element of a vector. It returns an iterator pointing to the first element of the vector.

Note: To use vector, include <vector> header.

Syntax

Syntax of vector::begin() function

vector::begin();

Parameter(s)

none – It accepts nothing.

Return value

iterator – It returns an iterator pointing to the first element of the vector.

Sample Input and Output

Input:
vector<int> vector1{ 1, 2, 3, 4, 5 };

Function call:
vector<int>::iterator it;
it = vector1.begin();
cout << *it;

Output:
1

C++ STL program to demonstrate example of vector::begin() function

//C++ STL program to demonstrate example of 
//vector::begin() function

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

int main()
{
    vector<int> v1;

    v1.push_back(10);
    v1.push_back(20);
    v1.push_back(30);
    v1.push_back(40);
    v1.push_back(50);

    //creating iterator
    vector<int>::iterator it;
    it = v1.begin();
    cout << "first element is: " << *it << endl;

    return 0;
}

Output

first element is: 10

Reference: C++ vector::begin()