Compilare: user.cpp: In function ‘vcd FFT_REV(const vcd&)’: user.cpp:101:8: warning: variable ‘cdn’ set but not used [-Wunused-but-set-variable] cd cdn = cd(n, 0); ^ user.cpp: In function ‘void mult(vcd&, vcd&)’: user.cpp:126:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < A_pv.size(); ++i) ^ user.cpp: In function ‘void read()’: user.cpp:25:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:27:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &x); ^ user.cpp:31:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &m); ^ user.cpp:33:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &x); ^ user.cpp: In function ‘int main()’: user.cpp:133:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bacterii2.in", "r", stdin); ^ user.cpp:134:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bacterii2.out", "w", stdout); ^ user.cpp:137:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &t); ^