Compilare: user.cpp: In function ‘int in_hash(int)’: user.cpp:15:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < V[x % mod].size(); ++ i) ^ user.cpp: In function ‘void read()’: user.cpp:23:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("brazi.in", "r", stdin); ^ user.cpp:24:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("brazi.out", "w", stdout); ^ user.cpp:25:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &t); ^ user.cpp:28:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:33:42: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &x, &y, &z); ^ user.cpp:41:15: warning: ‘r’ may be used uninitialized in this function [-Wmaybe-uninitialized] dfs(r); ^