# valarray sum() Function in C++ with Examples

C++ valarray sum() Function: Here, we will learn about the sum() function, its usages, syntax and examples.
Submitted by Shivang Yadav, on May 08, 2022

The valarray class in C++ is a special container that is used for holding elements like an array and performing operations on them.

## std::valarray<T>::sum() Function

The sum() function is defined in valarray class, and it returns the sum of all the elements of the valarray, as if calculated by applying operator+= to a copy of one element and all the other elements, in an unspecified order.

Syntax:

```T sum() const;

// or
valarray.sum()
```

Parameter(s): The method does not require any parameter.

Return Value: The method returns a single value with the same type as the element of the valarray.

## C++ valarray sum() Function Example 1:

```#include <iostream>
#include <valarray>
using namespace std;

int main()
{
// Declaring valarray
valarray<int> myvalarr = { 1, 2, 3, 4, 5, 6, 7 };

// Printing the elements of valarray
cout << "The elements stored in valarray are : ";
for (int& ele : myvalarr)
cout << ele << " ";

// Calculating the sum of all elements of valarray
cout << "\nThe sum of all elements of valarray is ";
cout << myvalarr.sum();

return 0;
}
```

Output:

```The elements stored in valarray are : 1 2 3 4 5 6 7
The sum of all elements of valarray is 28
```

## C++ valarray sum() Function Example 2:

```// Program to find the type of summed value

#include <iostream>
#include <valarray>
#include <typeinfo>
using namespace std;

int main()
{
// Declaring valarray
valarray<float> myvalarr = { 1, 2, 3, 4, 5, 6, 7.4 };

// Printing the elements of valarray
cout << "The elements stored in valarray are : ";
for (float& ele : myvalarr)
cout << ele << " ";

// Calculating the sum of all elements of valarray
cout << "\nThe type of summed values is ";
cout << typeid(myvalarr.sum()).name();

return 0;
}
```

Output:

```The elements stored in valarray are : 1 2 3 4 5 6 7.4
The type of summed values is f
```

Preparation