module.cpp: In function 'void read_input()': module.cpp:13: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result module.cpp:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result module.cpp:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result module.cpp: In function 'void write_output()': module.cpp:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result module.cpp: In function 'void get_rec_modules(const std::vector<int, std::allocator<int> >&, const std::vector<int, std::allocator<int> >&, int, std::vector<std::vector<int, std::allocator<int> >, std::allocator<std::vector<int, std::allocator<int> > > >*)': module.cpp:120: warning: comparison between signed and unsigned integer expressions module.cpp:123: warning: comparison between signed and unsigned integer expressions module.cpp:128: warning: comparison between signed and unsigned integer expressions module.cpp:170: warning: comparison between signed and unsigned integer expressions module.cpp:173: warning: comparison between signed and unsigned integer expressions module.cpp:175: warning: comparison between signed and unsigned integer expressions module.cpp: In function 'void get_modules(const std::vector<int, std::allocator<int> >&, int, std::vector<std::vector<int, std::allocator<int> >, std::allocator<std::vector<int, std::allocator<int> > > >*)': module.cpp:194: warning: comparison between signed and unsigned integer expressions module.cpp: In function 'void dfs(int, const std::vector<int, std::allocator<int> >&, std::vector<int, std::allocator<int> >*)': module.cpp:242: warning: comparison between signed and unsigned integer expressions module.cpp: In function 'void get_connected_components(const std::vector<int, std::allocator<int> >&, std::vector<std::vector<int, std::allocator<int> >, std::allocator<std::vector<int, std::allocator<int> > > >*)': module.cpp:253: warning: comparison between signed and unsigned integer expressions module.cpp: In function 'int num_modules(const std::vector<int, std::allocator<int> >&)': module.cpp:285: warning: comparison between signed and unsigned integer expressions module.cpp:286: warning: comparison between signed and unsigned integer expressions module.cpp:296: warning: comparison between signed and unsigned integer expressions module.cpp:300: warning: comparison between signed and unsigned integer expressions module.cpp:310: warning: comparison between signed and unsigned integer expressions module.cpp:315: warning: comparison between signed and unsigned integer expressions module.cpp:319: warning: comparison between signed and unsigned integer expressions module.cpp:322: warning: comparison between signed and unsigned integer expressions module.cpp:325: warning: comparison between signed and unsigned integer expressions module.cpp:342: warning: comparison between signed and unsigned integer expressions