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0_0_1637872_9186.cpp: In function `int main()':
0_0_1637872_9186.cpp:149: error: redefinition of `int main()'
0_0_1637872_9186.cpp:57: error: `int main()' previously defined here
0_0_1637872_9186.cpp:179: error: no matching function for call to `sort(__gnu_cxx::__normal_iterator<Node*, std::vector<Node, std::allocator<Node> > >, __gnu_cxx::__normal_iterator<Node*, std::vector<Node, std::allocator<Node> > >, <unknown type>)'