Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:39:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<g[x].size();++i) ^ user.cpp: In function ‘int main()’: user.cpp:64:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int q=0;q<h[j].size();++q) ^ user.cpp:46:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("autobuze.in","r",stdin); ^ user.cpp:47:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("autobuze.out","w",stdout); ^ user.cpp:49:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:52:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[i]); ^