Compilare: main.cpp: In function 'lint solve(std::vector<int>&)': main.cpp:173:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < allNodes.size(); ++ i) { ~~^~~~~~~~~~~~~~~~~ main.cpp: In constructor 'InputReader::InputReader(const char*)': main.cpp:17:35: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buffer, 1, SIZE, in); ^ main.cpp: In member function 'void InputReader::advance()': main.cpp:40:39: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buffer, 1, SIZE, in); ^