View Compilation Error

0_0_4576726_12570.cpp: In function `int main()':
0_0_4576726_12570.cpp:89: error: no match for 'operator=' in 'pt = 0'
GCC/bin/../lib/gcc/mingw32/3.4.2/../../../../include/c++/3.4.2/bits/stl_iterator.h:587: note: candidates are: __gnu_cxx::__normal_iterator<int*, std::vector<int, std::allocator<int> > >& __gnu_cxx::__normal_iterator<int*, std::vector<int, std::allocator<int> > >::operator=(const __gnu_cxx::__normal_iterator<int*, std::vector<int, std::allocator<int> > >&)