Compilare: user.cpp: In function ‘void read()’: user.cpp:41: warning: unused variable ‘x’ user.cpp:45: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:49: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘int rad(int)’: user.cpp:69: warning: statement has no effect user.cpp: In function ‘void pre()’: user.cpp:104: warning: unused variable ‘cos’ user.cpp: In function ‘void solve()’: user.cpp:146: warning: unused variable ‘j’ user.cpp:151: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result