Compilare: main.cpp: In function 'void dfs1(int, int)': main.cpp:61:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int it = 0; it < edg[x].size(); ++it) { ~~~^~~~~~~~~~~~~~~ main.cpp: In member function 'void InputReader::advance()': main.cpp:16:43: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] ptx = 0; fread(buf, SIZE, 1, inFile); } ^ main.cpp: In constructor 'InputReader::InputReader(const char*)': main.cpp:29:32: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buf, SIZE, 1, inFile); ^