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0_0_12017854_9115.cpp: In function `int main()':
0_0_12017854_9115.cpp:35: error: no match for 'operator=' in 'it1 = (&s1)->std::set<_Key, _Compare, _Alloc>::erase [with _Key = long long int, _Compare = std::less<long long int>, _Alloc = std::allocator<long long int>](it1)'
GCC/bin/../lib/gcc/mingw32/3.4.2/../../../../include/c++/3.4.2/bits/stl_tree.h:220: note: candidates are: std::_Rb_tree_const_iterator<long long int>& std::_Rb_tree_const_iterator<long long int>::operator=(const std::_Rb_tree_const_iterator<long long int>&)