Compilare: main.cpp: In function 'void dfs(int)': main.cpp:105:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < G[node].size(); i++) { ~~^~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:283:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < Sol.size(); i++) ~~^~~~~~~~~~~~ main.cpp:293:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < Sol.size(); i++) ~~^~~~~~~~~~~~ main.cpp:297:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = i + 1; j < Sol.size(); j++) ~~^~~~~~~~~~~~ main.cpp: In constructor 'InputReader::InputReader(const char*)': main.cpp:29:42: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buff,SIZE,1,input_file); ^ main.cpp: In member function 'void InputReader::advance()': main.cpp:79:46: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buff,SIZE,1,input_file); ^