Compilare: user.cpp: In function ‘int main()’: user.cpp:180:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen( "zeap.in" , "r", stdin ); ^ user.cpp:181:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen( "zeap.out", "w", stdout ); ^ user.cpp:189:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf( "%d", &X ); ^ user.cpp:194:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf( "%d", &X ); ^ user.cpp:203:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf( "%d", &X ); ^ user.cpp: In member function ‘int nrx_treap::delete_node(nrx_treap::treap_node*&, int)’: user.cpp:116:17: warning: ‘ok’ may be used uninitialized in this function [-Wmaybe-uninitialized] int ok; ^ user.cpp: In function ‘int main()’: user.cpp:195:47: warning: ‘ok’ may be used uninitialized in this function [-Wmaybe-uninitialized] ok = my_treap.delete_node( X ); ^