Compilare: user.cpp: In function ‘void firstDFS(int)’: user.cpp:28:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<G[node].size(); ++i) ^ user.cpp: In function ‘void secondDFS(int)’: user.cpp:55:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<G[node].size(); ++i) ^ user.cpp: In function ‘char getChar()’: user.cpp:97:41: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] pos = 0, fread(buf, 1, BUF, fin); ^