# C++ Algorithm Library - find() Function

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## Description

The C++ function std::algorithm::find() finds the first occurrence of the element. It uses operator = for comparison.

## Declaration

Following is the declaration for std::algorithm::find() function form std::algorithm header.

### C++98

```template <class InputIterator, class T>
InputIterator find (InputIterator first, InputIterator last, const T& val);
```

## Parameters

• first − Input iterator to the initial position.

• last − Input iterator to the final position.

• val − Value to compare the elements.

## Return value

If element found it returns an iterator pointing to the first occurrence of the element otherwise returns last.

## Exceptions

Throws exception if either element comparison or an operation on an iterator throws exception.

Please note that invalid parameters cause undefined behavior.

Linear.

## Example

The following example shows the usage of std::algorithm::find() function.

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

using namespace std;

int main(void) {
int val = 5;
vector<int> v = {1, 2, 3, 4, 5};

auto result = find(v.begin(), v.end(), val);

if (result != end(v))
cout << "Vector contains element " << val << endl;

val = 15;

result = find(v.begin(), v.end(), val);

if (result == end(v))
cout << "Vector doesn't contain element " << val << endl;

return 0;
}
```

Let us compile and run the above program, this will produce the following result −

```Vector contains element 5
Vector doesn't contain element 15
```
algorithm.htm