<vector> problem

[revit]

I use the &lt;vector&gt; data structure from std.
the program is compiled without no errors, but when i run it with an input i get -Segmentation fault (core dumped).
i run it with debugger and descovered that in one point when i come to the line: MyVector.push_back(NULL);
the program gives me an error and jump to a file called :
Dbgheap.c - this happens after several times the program did MyVector.push_back(NULL); seccessfully.

please help!
Thanks!

[NMTop40]

you've probably committed a memory violation elsewhere which has invalidated your heap. this is often writing over the bounds of an array.

sometimes the error doesn't show up until later on.