Cannot increment end map/set iterator
WebMay 29, 2011 · Your algorithm is flawed because you did not understood what erase returned.. When you use erase, it removes the element pointing to by the iterator, and returns an iterator to the next element.. If you wish to iterate over all elements of a list, it means that whenever erase was used you should not further increment it.. This is the … WebMar 4, 2024 · _STL_VERIFY (this->_Getcont (), "cannot increment value-initialized map/set iterator"); According to the call back, this line of the actual code seems to be what triggers it: for (map>::iterator it = m_taskreports.begin (); it != m_taskreports.end (); ++it) {
Cannot increment end map/set iterator
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WebIn fact, you should always use std::next, since it knows which iterator category its argument has and what the most efficient way to compute the next iterator is. That way, you don't have to care about the specific container you happen to be using. Share Improve this answer Follow answered Mar 2, 2015 at 21:49 Kerrek SB 460k 91 869 1075 WebJun 5, 2024 · When all_targets.insert is called, the "it" gets invalid because the memory allocation changed in all_targets, so the next ++it generate an assertion failure. Working with indexes solves the problem Here's the fixed version:
WebIn this question asking how to adjust the iterator to an STL container by 2 elements two different approaches are offered: either use a form of arithmetic operator - +=2 or ++ twice or use std::advance () I've tested both of them with VC++ 7 for the edge case when the iterator points onto the last element of the STL container or beyond: WebSep 3, 2024 · 3 Answers. Sorted by: 8. You're providing an empty std::vector as the destination while calling std::copy (), hence it'll potentially be too small to fit the source data, and so you get undefined behavior. To solve this directly you need to pass a std::back_inserter as the 3rd argument to std::copy (). That way it will append to the …
WebDec 19, 2024 · std::map::iterator it_mp = mp.find (key); This accesses the contents of the multimap, without the protection of a mutex. The other execution thread is modifying this map, concurrently. This is undefined behavior. Neither std::map, nor any other container in the C++ library, is thread-safe. WebMar 30, 2024 · Because it is an iterator to the extracted element, it is now invalid. Subsequent attempts to use it (with it++ to advance the loop iteration) leads to …
WebJun 27, 2013 · I believe the problem is that you increment the value somewhere along the way without noticing, the error means you are trying to dereference the end () iterator. Have a look at this code i believe it is pretty similar to yours and as you can see it worked fine.
WebDec 8, 2024 · for(map::iterator beast = farm.begin(); beast!=farm.end(); ++beast) Btw there is no way that the compiler can know that you want map::iterator beast to be an iterator for farm, of course you need to get an iterator from the container and not just create an iterator and assume it points to the … how to set a rule in outlook to forward emailWebWhat you can do is use the iterator returned by std::map::insert: auto result = my_map.insert (move (handle)); it = make_reverse_iterator (result.position); paddy 56258 score:0 As pointed by @paddy, after calling .extract () method and doing .insert () again all your iterators are invalidated hence you can't run modifying loop any further. how to set a screensaver on pcWebJan 25, 2012 · You can resolve the problem by removing loop expression and moving it into an else statement: while (it != m_DriverList.end ()) { if (it->second == this) { … how to set as defaultWebOct 4, 2014 · Based on the fact that it++ is acceptable, we should define a new iterator called itplusone, which is initialized as itplusone = ++it. In this way, you can safely use the meaning of an iterator pointing to the next item of it. Also clearly, the range of iterator of itplusone bounded by terms itplusone != set.end (). how to set a scale in cadWebDec 31, 2013 · When comparing iterators, both of the multimap iterators must come from the same container; since you're getting a new copy each time you call GetTasks (), you violate this constraint, and this is the source of your error. how to set a schlage keypad lockWebJul 5, 2024 · Using the iterator returned from erase is the right thing to do, but that iterator references the element past the one erased, hence you should only increment when you do not erase: for (it = ms.begin (); it != ms.end (); ) { // do not increment here if (i == 4) { it = ms.erase (it); } else { ++it; // but only when you do not erase } ++i; } how to set a schedule on hive appWebMay 3, 2024 at 18:20 Anyway there is a special iterator value called the end of list iterator. It indicates a position past the end of the list. But there is no data at this position, so you aren't supposed to dereference the end of list iterator. But somewhere that's exactly what your program is doing. – john May 3, 2024 at 18:22 how to set a scale in sketchup