Use partial_sum to convert elements in a container into absolute values
/* 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; int main() { vector<int> coll; coll.push_back(17); coll.push_back(-3); coll.push_back(22); coll.push_back(13); coll.push_back(13); coll.push_back(-9); PRINT_ELEMENTS(coll,"coll: "); // convert into absolute values partial_sum (coll.begin(), coll.end(), // source coll.begin()); // destination PRINT_ELEMENTS(coll,"absolute: "); } /* coll: 17 -3 22 13 13 -9 absolute: 17 14 36 49 62 53 */