find() in C++ STL

The C++ Standard Library consists of the header, <algorithm> which defines a collection of functions (principally designed to deal with a range of elements). find() is a method in the STL that returns an iterator pointing to the first element in the range which in equal to a certain value. If no element is found, the method returns the last iterator.

Syntax:

find( iterator_begin, iterator_end, val );

Parameters: The find() method accepts 3 parameters

• iterator_begin: Iterator to the initial position
• iterator_end: Iterator to the final position ( Note: the range is [iterator_begin,iterator_end) )
• val: Value to match

Return value: Iterator pointing to the first element in the range which is equal to val. iterator_end if val not found

Example of find() method

#include <iostream>
#include <algorithm>
#include <vector>

using namespace std;


int main()
{
    vector<int> v;
    v.push_back(1);
    v.push_back(2);
    v.push_back(3);
    v.push_back(4);
    v.push_back(3);
    v.push_back(5);
    v.push_back(3);

    vector<int>::iterator it = find(v.begin(), v.end(), 4);
    cout<<"Index of the element 4 is: "<< distance(v.begin(), it) << endl;
}

Output:

Index of the element 4 is: 3