Apache C++ Standard Library Reference Guide

## find()

Library:  Algorithms

`Function`

No Entries

### Summary

Algorithm that finds an occurrence of value in a sequence

### Synopsis

```#include <algorithm>

namespace std {
template <class InputIterator, class T>
InputIterator find(InputIterator start,
InputIterator finish,
const T& value);
}
```

### Description

The find() algorithm lets you search for the first occurrence of a particular value in a sequence. find() returns the first iterator i in the range [start, finish) for which the following condition holds:

*i == value.

If find() does not find a match for value, it returns the iterator finish.

Type T must be EqualityComparable.

### Complexity

find() performs at most finish - start comparisons.

### Example

```//
//  find.cpp
//

#include <vector>      // for vector
#include <algorithm>   // for adjacent_find, find
#include <functional>  // for bind1st, equal_to
#include <iostream>    // for cout, endl

int main ()
{
// Typedef for convenience.
typedef std::vector<int, std::allocator<int> > Vector;

const Vector::value_type arr[] = { 0, 1, 2, 2, 3,
4, 2, 2, 6, 7 };

// Set up a vector.
const Vector v1 (arr, arr + sizeof arr / sizeof *arr);

// Try find.
Vector::const_iterator it = std::find (v1.begin (),
v1.end (), 3);

std::cout << *it << ' ';

// Try find_if.
it = std::find_if (v1.begin (), v1.end (),
std::bind1st (std::equal_to<Vector::value_type>(),
3));

std::cout << *it << ' ';

it = std::adjacent_find (v1.begin (), v1.end ());

std::cout << *it << ' ';

it = std::adjacent_find (v1.begin (), v1.end (),
std::equal_to<Vector::value_type>());

std::cout << *it << std::endl;

return 0;
}
Program Output

3 3 2 2
```