Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:19:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<e[x].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:36:27: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%d",&n,&m); ^ user.cpp:45:30: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&x); ^