Eroare de compilare: user.cpp:4:9: error: macro names must be identifiers user.cpp:5:9: error: macro names must be identifiers user.cpp:86:2: warning: no newline at end of file user.cpp: In function 'void open()': user.cpp:18: error: 'input' was not declared in this scope user.cpp:19: error: 'output' was not declared in this scope user.cpp: In function 'void read()': user.cpp:23: warning: unused variable 'a' user.cpp: In function 'void dfs1(int)': user.cpp:37: warning: comparison between signed and unsigned integer expressions user.cpp: In function 'void dfs2(int)': user.cpp:51: warning: comparison between signed and unsigned integer expressions