multiplies Struct

结构提供执行算术运算相乘在指定值类型元素的预定义的函数对象。

template<class Type>
   struct multiplies : public binary_function <Type, Type, Type> 
   {
      Type operator()(
         const Type& _Left, 
         const Type& _Right
      ) const;
   };

参数

  • _Left
    是参数类型 *** 类型 *** 将乘以函数对象的数字。

  • _Right
    是参数类型 *** 类型 *** 将乘以函数对象的数字。

返回值

乘法 _Left * _Right的产品。

示例

// 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;
}
  

要求

标头: <functional>

命名空间: std

请参见

参考

线程安全性对标准C++库中

标准模板库