generate (STL Samples)

Illustrates how to use the generate Standard Template Library (STL) function in Visual C++.

template<class InputIterator, class Function> inline
   Function for_each(
      InputIterator First,
      InputIterator Last,
      Function F
   )
template<class ForwardIterator, class Generator> inline
   void generate(
      ForwardIterator First,
      ForwardIterator Last,
      Generator Gen
   )

Remarks

Note

The class/parameter names in the prototype do not match the version in the header file. Some have been modified to improve readability.

The generate algorithm traverses the range [First, Last + 1), assigning to each element the value returned by Gen. generate modifies the elements in the specified range.

Example

// generate.cpp
// compile with: /EHsc
//
// Functions:
//   generate - Fill a sequence using a generator function
//   Fibonacci - return the next Fibonacci number in the
//               Fibonacci series.

// disable warning C4786: symbol greater than 255 characters,
// okay to ignore
#pragma warning(disable: 4786)

#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

// return the next Fibonacci number in the
// Fibonacci series.
int Fibonacci(void)
{
    static int r;
    static int f1 = 0;
    static int f2 = 1;
    r = f1 + f2 ;
    f1 = f2 ;
    f2 = r ;
    return f1 ;
}

int main()
{
    const int VECTOR_SIZE = 8 ;

    // Define a template class vector of integers
    typedef vector<int > IntVector ;

    //Define an iterator for template class vector of integer
    typedef IntVector::iterator IntVectorIt ;

    IntVector Numbers(VECTOR_SIZE) ;   //vector containing numbers

    IntVectorIt start, end, it ;

    start = Numbers.begin() ;   // location of first
                                // element of Numbers

    end = Numbers.end() ;       // one past the location
                                // last element of Numbers


    // fill the range [first, last +1) with a series of
    // Fibonnaci numbers using the Fibonacci function
    generate(start, end, Fibonacci) ;

    // print content of Numbers
    cout << "Numbers { " ;
    for(it = start; it != end; it++)
        cout << *it << " " ;
    cout << " }\n" << endl ;
}

Output

Numbers { 1 1 2 3 5 8 13 21  }

Requirements

Header: <algorithm>

See Also

Concepts

Standard Template Library Samples