Compilare: user.cpp: In function ‘void input()’: user.cpp:53:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d" , &n ) ; ^ user.cpp:57:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d%d" , &x , &y ) ; ^ user.cpp: In function ‘int main()’: user.cpp:77:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ( "arbore7.in" , "r" , stdin ) ; ^ user.cpp:78:46: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ( "arbore7.out" , "w" , stdout ) ; ^