The Modern C++ Challenge

54. Pairwise algorithm

The pairwise function proposed for this problem must pair adjacent elements of an input range and produce std::pair elements that are added to an output range. The following code listing provides two implementations:

• A general function template that takes iterators as arguments: a begin and end iterator define the input range, and an output iterator defines the position in the output range where the results are to be inserted
• An overload that takes an std::vector<T> as the input argument and returns an std::vector<std::pair<T, T>> as the result; this one simply calls the first overload:

template <typename Input, typename Output>void pairwise(Input begin, Input end, Output result){   auto it = begin; while (it != end) ...