for_each


template function
<algorithm> 
template <class InputIterator, class Function>
   Function for_each (InputIterator first, InputIterator last, Function f);

Apply function to range

Applies function f to each of the elements in the range [first,last).

The behavior of this template function is equivalent to:
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template<class InputIterator, class Function>
  Function for_each(InputIterator first, InputIterator last, Function f)
  {
    for ( ; first!=last; ++first ) f(*first);
    return f;
  }



Parameters

first, last
Input iterators to the initial and final positions in a sequence. The range used is [first,last), which contains all the elements between first and last, including the element pointed by first but not the element pointed by last.
f
Unary function taking an element in the range as argument. This can either be a pointer to a function or an object whose class overloads operator().
Its return value, if any, is ignored.


Return value

The same as f.

Example

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// for_each example
#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;

void myfunction (int i) {
  cout << " " << i;
}

struct myclass {
  void operator() (int i) {cout << " " << i;}
} myobject;

int main () {
  vector<int> myvector;
  myvector.push_back(10);
  myvector.push_back(20);
  myvector.push_back(30);

  cout << "myvector contains:";
  for_each (myvector.begin(), myvector.end(), myfunction);

  // or:
  cout << "\nmyvector contains:";
  for_each (myvector.begin(), myvector.end(), myobject);

  cout << endl;

  return 0;
}


Output:
myvector contains: 10 20 30
myvector contains: 10 20 30


Complexity

Linear: Applies f once to each element.

See also

transform Apply function to range (function template)
find Find value in range (function template)
search Find subsequence in range (function template)