# multiplies Struct

Visual Studio 2015

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A predefined function object that performs the multiplication operation (binary `operator*`) on its arguments.

## Syntax

```template <class Type = void>
struct multiplies : public binary_function <Type, Type, Type>
{
Type operator()(
const Type& Left,
const Type& Right) const;

};

// specialized transparent functor for operator*
template <>
struct multiplies<void>
{
template <class T, class U>
auto operator()(T&& Left, U&& Right) const
->
decltype(std::forward<T>(Left)
* std::forward<U>(Right));

};

```

#### Parameters

`Type`, `T`, `U`
A type that supports a binary `operator*` that takes operands of the specified or inferred types.

`Left`
The left operand of the multiplication operation. The unspecialized template takes an lvalue reference argument of type `Type`. The specialized template does perfect forwarding of lvalue and rvalue reference arguments of inferred type `T`.

`Right`
The right operand of the multiplication operation. The unspecialized template takes an lvalue reference argument of type `Type`. The specialized template does perfect forwarding of lvalue and rvalue reference arguments of inferred type `U`.

## Return Value

The result of `Left``*``Right`. The specialized template does perfect forwarding of the result, which has the type that's returned by `operator*`.

## Example

```// functional_multiplies.cpp
// compile with: /EHsc
#include <vector>
#include <functional>
#include <algorithm>
#include <iostream>

using namespace std;

int main( )
{
vector <int> v1, v2, v3 ( 6 );
vector <int>::iterator Iter1, Iter2, Iter3;

int i;
for ( i = 1 ; i <= 6 ; i++ )
{
v1.push_back( 2 * i );
}

int j;
for ( j = 1 ; j <= 6 ; j++ )
{
v2.push_back( 3 * j );
}

cout << "The vector v1 = ( " ;
for ( Iter1 = v1.begin( ) ; Iter1 != v1.end( ) ; Iter1++ )
cout << *Iter1 << " ";
cout << ")" << endl;

cout << "The vector v2 = ( " ;
for ( Iter2 = v2.begin( ) ; Iter2 != v2.end( ) ; Iter2++ )
cout << *Iter2 << " ";
cout << ")" << endl;

// Finding the element-wise products of the elements of v1 & v2
transform ( v1.begin( ),  v1.end( ), v2.begin( ), v3.begin ( ),
multiplies<int>( ) );

cout << "The element-wise products of vectors V1 & v2\n are: ( " ;
for ( Iter3 = v3.begin( ) ; Iter3 != v3.end( ) ; Iter3++ )
cout << *Iter3 << " ";
cout << ")" << endl;
}
\* Output:
The vector v1 = ( 2 4 6 8 10 12 )
The vector v2 = ( 3 6 9 12 15 18 )
The element-wise products of vectors V1 & v2
are: ( 6 24 54 96 150 216 )
*\

```