Compilare: user.cpp: In function ‘void dfs(int, int, int, std::multiset<int, std::less<int>, std::allocator<int> >&, std::multiset<int, std::less<int>, std::allocator<int> >&)’: user.cpp:20: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:62: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:63: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:64: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:67: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void dfs(int, int, int, std::multiset<int, std::less<int>, std::allocator<int> >&, std::multiset<int, std::less<int>, std::allocator<int> >&)’: user.cpp:19: warning: ‘ermin’ may be used uninitialized in this function user.cpp:19: warning: ‘ermax’ may be used uninitialized in this function