Help:Orphaned code

Sometimes, articles get rearranged, or even repurposed, and code no longer fits in. This is a place where such code may be stored, rather than deleted outright.

C++

for_each

Compiler: g++ 4.1.1

 #include <iostream>  // std::cout, std::endl
 #include <vector>    // std::vector
 #include <algorithm> // std::for_each
 
 struct sum
 {
   int _sum;                                    
   sum() : _sum(0) {};                         // Initialize sum with 0;
   void operator() (int a) { _sum += a; }      // this function will be called for every element
 };
 
 int main()
 {
   std::vector<int> v;
   v.push_back(10);
   v.push_back(23);
   v.push_back(34);
 
   /* Note that for_each gets a fresh instance of sum passed,
    * applies every element beginning with *v.begin() up to,
    * but not including v.end() to the function object
    * and returns a copy of it.
    */
 
   sum the_sum = std::for_each(v.begin(), v.end(), sum());
 
   std::cout << "The sum is " << the_sum._sum << std::endl;
   return 0;
 }