Compilare: user.cpp: In function ‘int main()’: user.cpp:12:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zebughil.in","r",stdin); ^ user.cpp:13:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zebughil.out","w",stdout); ^ user.cpp:21:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&N,&G); ^ user.cpp:22:59: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(ans = 0, i = 1; i <= N; ++i) scanf("%d",&v[i]); ^