Delete a vector of pointers
WebJul 1, 2015 · For both array and vector, you need to delete each item (if they were allocated using new) before deleting the array and the vector. If you create the array like this Sample* arr [100]; for (int i = 0; i < 100; ++i) { arr [i] = new Sample (); } you need to delete them like this for (int i = 0; i < 100; ++i) { delete arr [i]; } WebNov 8, 2015 · Yes, but you need a functor: struct delete_ptr { template void operator () (T* pPtr) { delete pPtr; } }; std::for_each (objs.begin (), objs.end (), delete_ptr ()); In C++0x, lambda's help you make functors in-place: std::for_each (objs.begin (), objs.end (), [] (Obj* pPtr) { delete pPtr; });
Delete a vector of pointers
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WebOct 8, 2012 · Yes, the code has a memory leak unless you delete the pointers. If the foo class owns the pointers, it is its responsibility to delete them. You should do this before clearing the vector, otherwise you lose the handle to the memory you need to de … WebJun 15, 2011 · When moving pointers, you can just keep the pointer in a temporary variable, erase it from the vector, then insert wherever you need. And here's another simple way to delete and then remove all the items in a vector: template void purge ( std::vector & v ) { for ( auto item : v ) delete item; v.clear (); } Share Improve this …
WebMar 13, 2015 · In your allocation routine, you allocate twice the number of required MappedGraphicsItem . If you have N odd vertices, then you will allocate 2*N*N elements. The deletion routine is correct though. Rationale: The double for loop at the beginning is the cartesian product of odd_vertices with itself. WebDec 22, 2012 · I have a vector of Object pointers. I want to be able to delete those objects and free the memory taken up by those objects. What I have currently is this: This is the vector that contains the object pointers: std::vector List; This is the function that deletes the element in the vector and frees the memory:
WebJul 6, 2015 · Therefore, deleteing pointers in a vector, while most likely a very bad architectural decision and an invitation to pain and suffering with the debugger at 3:00 AM on a Saturday night, is perfectly legal. EDIT: Regarding Kranar's comment that "assigning a pointer to an invalid pointer value results in undefined behavior." No, this is incorrect.
WebNov 13, 2011 · As hamsterman said, a vector will delete itself (plus the storage it allocated) when it goes out of scope. You only need to clear vectors if you are reusing them, or - for …
WebIf I change the example so v becomes a pointer to a dynamically-allocated vector, you need to explicitly delete it, as the pointer going out of scope at 2 doesn't do that for you. It's better to use something like std::unique_ptr in that case, but if you don't and v is leaked, the storage it allocated will be leaked as well. grinch christmas baublesWebOct 2, 2012 · You do not need a second vector for the movies, just store the pointers and you can access them. Like Brian wrote, the vector would be defined as std::vector movies But be aware that the vector will not delete your objects afterwards, which will result in a memory leak. grinch christmas bathroom decorWebMar 21, 2014 · When you erase an item from a vector, the destructor of the item will be called. But in this case the item is a pointer, and pointers don't have destructors. The object the pointer is pointing to will not have its destructor called until you use delete on the pointer. If the pointer is erased and you don't have another copy of it, you'll never ... grinch christmas blanketWebNov 22, 2024 · Wrapping the pointers in smart pointers or using a specialist pointer container is, in general, going to be more robust. There are lots of ways that items can be removed from a list ( various flavours of erase , clear , destruction of the list, assignment via an iterator into the list, etc. ). fifty two thousand furnitureWeb54. std::vector does call the destructor of every element it contains when clear () is called. In your particular case, it destroys the pointer but the objects remain. Smart pointers are the right way to go, but be careful. auto_ptr cannot be used in std containers. boost::scoped_ptr can't either. boost::shared_ptr can, but it won't work in ... grinch christmas bedding king sizeWebwhile(!foo.empty()) delete foo.front(), foo.pop_front(); For std::vector use: while(!bar.empty()) delete bar.back(), bar.pop_back(); Not sure why i took front instead of back for std::list above. I guess it's the feeling that it's faster. But actually both are constant time :). Anyway wrap it into a function and have fun: fifty two thousand five hundredWebDec 28, 2011 · void deleteVectorOfPointers (T *vector) { typename T::iterator i; for (i = vector->begin (); i end (); ++i) { delete *i; } delete vector; } int main () { vector *myVector = new vector (); Foo *testObj = new Foo (); myVector->push_back (testObj); myVector->at (0)->bar (); deleteVectorOfPointers (myVector); testObj->bar (); return 0; } … fifty-two thousandths