Compilare: user.cpp: In function ‘int main()’: user.cpp:11:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("v2d.in","r",stdin); ^ user.cpp:12:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("v2d.out","w",stdout); ^ user.cpp:14:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&n,&t,&q); ^ user.cpp:16:51: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(int j=1;j<=n;j++) scanf("%d",&v[i][j]); ^