Compilare: user.cpp: In function ‘void Read(int&)’: user.cpp:58:36: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] void Read (int &x){scanf ("%d", &x);} ^ user.cpp: In function ‘int main()’: user.cpp:61:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("unlock.in", "r", stdin); ^ user.cpp:62:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("unlock.out", "w", stdout); ^