Compilare: user.cpp: In function ‘int main()’: user.cpp:32:12: warning: unused variable ‘x’ [-Wunused-variable] double x; ^ user.cpp:26:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("euro2.in", "r", stdin); ^ user.cpp:27:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("euro2.out", "w", stdout); ^ user.cpp:29:18: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &N); ^ user.cpp:33:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lf", &v[0][i]); ^