Compilare: user.cpp: In function ‘int main()’: user.cpp:21:11: warning: unused variable ‘i’ [-Wunused-variable] int n,i; ^ user.cpp:19:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("tamplar.in","r",stdin); ^ user.cpp:20:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("tamplar.out","w",stdout); ^ user.cpp:22:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d",&n); ^ user.cpp: In function ‘void prod(int*, int)’: user.cpp:15:13: warning: ‘i’ is used uninitialized in this function [-Wuninitialized] v[0] = i-1; ^