Compilare: user.cpp: In function ‘void dfs(int, int, int, int)’: user.cpp:35:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i1 = 0; i1 < V[n1].size(); i1++) ^ user.cpp:38:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i2 = 0; i2 < V[n2].size(); i2++) ^ user.cpp: In function ‘void rez()’: user.cpp:53:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j = 0; j < V[i].size(); j++) ^ user.cpp: In function ‘void cit()’: user.cpp:16:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &N); ^ user.cpp:19:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d", &x, &y); ^ user.cpp:23:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("\n"); ^ user.cpp:26:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%c ", &S[i]); ^ user.cpp: In function ‘int main()’: user.cpp:71:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("arbpal.in", "r", stdin); ^ user.cpp:72:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("arbpal.out", "w", stdout); ^