STL transform question

Applications Programming
1

Hi all,
I pass to the transform algorithm two vectors, and the suma function.

#include <algorithm>
#include <iostream>
#include <iterator>
#include <vector>
using namespace std;

class Duo{
    public:
    int one;
    int two;
};

Duo suma(Duo first, Duo last){
    Duo ret;
    ret.one=first.one+last.one;
    ret.two=first.two+last.two;
    return ret;
}

int main(){
  vector<Duo> vec1;
  vector<Duo> vec2;

Duo obj;
  for (int i=0; i<5; i++){
    obj.one=i;
    obj.two=i;
    vec1.push_back(obj);
  }
  transform(vec1.begin(),vec1.end(),vec2.begin(),suma);

  return 0;
}

When I compile it, I get the following error.

/usr/include/c++/4.5/bits/stl_algo.h||In function �_OIter std::transform(_IIter, _IIter, _OIter, _UnaryOperation)
 [with _IIter = __gnu_cxx::__normal_iterator<Duo*, std::vector<Duo> >, _OIter = 
__gnu_cxx::__normal_iterator<Duo*, std::vector<Duo> >, _UnaryOperation = Duo (*)(Duo, Duo)]':|
/home/rav/Desktop/bas/main.cpp:30|54|instantiated from here|

/usr/include/c++/4.5/bits/stl_algo.h|4688|error: too few arguments to function|
||=== Build finished: 1 errors, 0 warnings ===|

What am I'm doing wrong? How can I fix it?

thanks!!
santiagorf

2

I changed the call of transform algorithm to this:

transform(vec1.begin(),vec1.end(),vec2.begin(),vec1.begin(),suma);

and it worked. Also vec2 has to be of size 5.

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