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copied!<p><strong>Warning:</strong> <code>boost::zip_iterator</code> and <code>boost::combine</code> as of Boost 1.63.0 (2016 Dec 26) will cause undefined behavior if the length of the input containers are not the same (it may crash or iterate beyond the end).</p> <hr> <p>Starting from Boost 1.56.0 (2014 Aug 7) you could <a href="http://www.boost.org/doc/libs/release/libs/range/doc/html/range/reference/utilities/combine.html" rel="noreferrer">use <code>boost::combine</code></a> (the function exists in earlier versions but undocumented):</p> <pre><code>#include <boost/range/combine.hpp> #include <vector> #include <list> #include <string> int main() { std::vector<int> a {4, 5, 6}; double b[] = {7, 8, 9}; std::list<std::string> c {"a", "b", "c"}; for (auto tup : boost::combine(a, b, c, a)) { // <--- int x, w; double y; std::string z; boost::tie(x, y, z, w) = tup; printf("%d %g %s %d\n", x, y, z.c_str(), w); } } </code></pre> <p>This would print </p> <pre> 4 7 a 4 5 8 b 5 6 9 c 6 </pre> <hr> <p>In earlier versions, you could define a range yourself like this:</p> <pre><code>#include <boost/iterator/zip_iterator.hpp> #include <boost/range.hpp> template <typename... T> auto zip(T&&... containers) -> boost::iterator_range<boost::zip_iterator<decltype(boost::make_tuple(std::begin(containers)...))>> { auto zip_begin = boost::make_zip_iterator(boost::make_tuple(std::begin(containers)...)); auto zip_end = boost::make_zip_iterator(boost::make_tuple(std::end(containers)...)); return boost::make_iterator_range(zip_begin, zip_end); } </code></pre> <p>The usage is the same.</p>

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