Compilare: user.cpp: In function ‘void d(int)’: user.cpp:9:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<v[x].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:20:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("flori.in","r",stdin); ^ user.cpp:21:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("flori.out","w",stdout); ^ user.cpp:22:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d", &n, &m); ^ user.cpp:25:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &b[i]); ^ user.cpp:28:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &y); ^