Compilare: user.cpp: In function ‘int dfs(int)’: user.cpp:13:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < V[x].size(); ++ i) ^ user.cpp:8:12: warning: unused variable ‘nod’ [-Wunused-variable] int i, nod, len = 0, ans = 0; ^ user.cpp: In function ‘void solve()’: user.cpp:41:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j; ^ user.cpp: In function ‘void read()’: user.cpp:26:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dominouri.in", "r", stdin); ^ user.cpp:27:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:30:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &x); ^ user.cpp:34:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &y); ^ user.cpp: In function ‘void solve()’: user.cpp:43:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &v[i]); ^ user.cpp: In function ‘void write()’: user.cpp:47:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dominouri.out", "w", stdout); ^