Use transform function to square all elements in an array : transform « STL Algorithms Modifying sequence operations « C++ Tutorial

1. C++ Tutorial
2. STL Algorithms Modifying sequence operations
3. transform

/* 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 <algorithm>
#include <functional>
#include <iterator>
using namespace std;

int main()
{
    int coll[] = { 5, 6, 2, 4, 1, 3 };

    // square all elements
    transform (coll, coll+6,        // first source
               coll,                // second source
               coll,                // destination
               multiplies<int>());  // operation

    // print all elements
    copy (coll, coll+6,
          ostream_iterator<int>(cout," "));
    cout << endl;
}

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