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0_0_28352502_11960.cpp: In function 'int dfs2(int)':
0_0_28352502_11960.cpp:70:23: error: request for member 'v' in 'g[u].std::vector<_Tp, _Alloc>::operator[]<int, std::allocator<int> >(((std::vector<int>::size_type)i))', which is of non-class type '__gnu_cxx::__alloc_traits<std::allocator<int> >::value_type {aka int}'
         int v=g[u][i].v;
                       ^