Compilare: user.cpp: In function ‘void read()’: user.cpp:20: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:23: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void bfs_X()’: user.cpp:35: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void bfs_Y()’: user.cpp:56: warning: comparison between signed and unsigned integer expressions