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    <p>There is nothing like this in the standard. Cycles don't play well with C++ iterators because a sequence representing the entire cycle would have <code>first == last</code> and hence be the empty sequence.</p> <p>Possibly you could introduce some state into the iterator, a Boolean flag to represent "not done yet." The flag participates in comparison. Set it <code>true</code> before iterating and to <code>false</code> upon increment/decrement.</p> <p>But it might just be better to manually write the algorithms you need. Once you've managed to represent the whole cycle, representing an empty sequence might have become impossible.</p> <p><strong>EDIT:</strong> Now I notice that you specified the number of cycles. That makes a big difference.</p> <pre><code>template&lt; class I &gt; class cyclic_iterator /* : public iterator&lt; bidirectional, yadda yadda &gt; */ { I it, beg, end; int cnt; cyclic_iterator( int c, I f, I l ) : it( f ), beg( f ), end( l ), cnt( c ) {} public: cyclic_iterator() : it(), beg(), end(), cnt() {} cyclic_iterator &amp;operator++() { ++ it; if ( it == end ) { ++ cnt; it = beg; } } // etc for --, post-operations friend bool operator== ( cyclic_iterator const &amp;lhs, cyclic_iterator const &amp;rhs ) { return lhs.it == rhs.it &amp;&amp; lhs.cnt == rhs.cnt; } // etc for != friend pair&lt; cyclic_iterator, cyclic_iterator &gt; cycle_range ( int c, I f, I l ) {//factory function, better style outside this scope return make_pair( cyclic_iterator( 0, f, l ), cyclic_iterator( c, f, l ) ); } }; </code></pre>
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    1. POIs there a standard cyclic iterator in C++
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    1. POIs there a standard cyclic iterator in C++
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    1. COI think for cyclic iterators, `last` would be inequal to any other iterator, since it’s a (pseudo-)infinite sequence …
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      1. USKonrad Rudolph
    2. CO@Konrad: then everything in `<algorithm>` would be useless, and indeed you wouldn't have a compliant iterator at all.
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    3. CO@Potatocorn: “everything in `<algorithm>` would be useless.” Yes, that’s the nature of cyclic/infinite sequences. But *other* things work very well with them. A lot of frameworks use them without problem. “you wouldn't have a compliant iterator at all.” What gives you that idea? Nothing in the standard says so. In fact, input iterators *are* pseudo-infinite and have many of the same properties.
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