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copied!<p>Doing this eagerly and only with copying is pretty easy:</p> <pre><code>#include <vector> #include <tuple> #include <algorithm> template<class... Ts> std::vector<std::tuple<Ts...>> zip(std::vector<Ts> const&... vs){ auto lo = std::min({vs.size()...}); std::vector<std::tuple<Ts...>> v; v.reserve(lo); for(unsigned i = 0; i < lo; ++i) v.emplace_back(vs[i]...); return v; } </code></pre> <p><a href="https://ideone.com/wyVCwj">Live example.</a></p> <p>With perfect forwarding and allowing moves out of the vector, it becomes just a bit more complicated, mostly due to the helpers:</p> <pre><code>#include <vector> #include <tuple> #include <algorithm> #include <type_traits> template<class T> using Invoke = typename T::type; template<class T> using Unqualified = Invoke<std::remove_cv<Invoke<std::remove_reference<T>>>>; template<class T> using ValueType = typename Unqualified<T>::value_type; template<class T> T const& forward_index(std::vector<T> const& v, unsigned i){ return v[i]; } template<class T> T&& forward_index(std::vector<T>&& v, unsigned i){ return std::move(v[i]); } template<class... Vs> std::vector<std::tuple<ValueType<Vs>...>> zip(Vs&&... vs){ auto lo = std::min({vs.size()...}); std::vector<std::tuple<ValueType<Vs>...>> v; v.reserve(lo); for(unsigned i = 0; i < lo; ++i) v.emplace_back(forward_index(std::forward<Vs>(vs), i)...); return v; } </code></pre> <p><a href="https://ideone.com/tnVX2r">Live example.</a></p>

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