Compilare: user.cpp: In function ‘int main()’: user.cpp:37:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("alpin.in","r",stdin); ^ user.cpp:38:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("alpin.out","w",stdout); ^ user.cpp:39:15: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:43:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&(v[i][j])); ^ user.cpp:56:10: warning: ‘y’ may be used uninitialized in this function [-Wmaybe-uninitialized] drum(x,y); ^ user.cpp:56:10: warning: ‘x’ may be used uninitialized in this function [-Wmaybe-uninitialized]