Compilare: user.cpp: In function ‘int main()’: user.cpp:227:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("divizori2.in","r",stdin); ^ user.cpp:228:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("divizori2.out","w",stdout); ^ user.cpp:230:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:232:30: 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 ‘bool solve(int)’: user.cpp:218:13: warning: ‘*((void*)(& must)+24).Hasher::v3’ may be used uninitialized in this function [-Wmaybe-uninitialized] if ( !(must.second == aux.second) ) return false; ^