Compilare: user.cpp: In function ‘void topologica()’: user.cpp:28: warning: comparison between signed and unsigned integer expressions user.cpp:44: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void df(int)’: user.cpp:59: warning: comparison between signed and unsigned integer expressions user.cpp:69: warning: comparison between signed and unsigned integer expressions user.cpp:77: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:84: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:85: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:87: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:89: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:93: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result