/* The following code example is taken from the book
* "The C++ Standard Library - A Tutorial and Reference"
* by Nicolai M. Josuttis, Addison-Wesley, 1999
*
* (C) Copyright Nicolai M. Josuttis 1999.
* Permission to copy, use, modify, sell and distribute this software
* is granted provided this copyright notice appears in all copies.
* This software is provided "as is" without express or implied
* warranty, and with no claim as to its suitability for any purpose.
*/
#include <iostream>
#include <vector>
#include <deque>
#include <list>
#include <set>
#include <map>
#include <string>
#include <algorithm>
#include <iterator>
#include <functional>
#include <numeric>
/* PRINT_ELEMENTS()
* - prints optional C-string optcstr followed by
* - all elements of the collection coll
* - separated by spaces
*/
template <class T>
inline void PRINT_ELEMENTS (const T& coll, const char* optcstr="")
{
typename T::const_iterator pos;
std::cout << optcstr;
for (pos=coll.begin(); pos!=coll.end(); ++pos) {
std::cout << *pos << ' ';
}
std::cout << std::endl;
}
/* INSERT_ELEMENTS (collection, first, last)
* - fill values from first to last into the collection
* - NOTE: NO half-open range
*/
template <class T>
inline void INSERT_ELEMENTS (T& coll, int first, int last)
{
for (int i=first; i<=last; ++i) {
coll.insert(coll.end(),i);
}
}
using namespace std;
// function object that adds the value with which it is initialized
template <class T>
class AddValue {
private:
T theValue; // value to add
public:
// constructor initializes the value to add
AddValue (const T& v) : theValue(v) {
}
// the function call for the element adds the value
void operator() (T& elem) const {
elem += theValue;
}
};
int main()
{
vector<int> coll;
INSERT_ELEMENTS(coll,1,9);
// add ten to each element
for_each (coll.begin(), coll.end(), // range
AddValue<int>(10)); // operation
PRINT_ELEMENTS(coll);
// add value of first element to each element
for_each (coll.begin(), coll.end(), // range
AddValue<int>(*coll.begin())); // operation
PRINT_ELEMENTS(coll);
}
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