Compilare: user.cpp: In function ‘int main()’: user.cpp:51:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<A.size (); i++) ^ user.cpp:61:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<A.size (); i++) ^ user.cpp:64:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i != A.size () - 1 && (tata (x) == tata (y) && sz[tata (x)] == 1)) ^ user.cpp:23:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("turism.in", "r", stdin); ^ user.cpp:24:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("turism.out", "w", stdout); ^ user.cpp:26:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d", &N, &M); ^ user.cpp:32:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d", &x, &y); ^