Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:31:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<v[nod].size();i++) ~^~~~~~~~~~~~~~ user.cpp:33:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<v[nod].size();i++) ~^~~~~~~~~~~~~~ user.cpp: In function ‘int main()’: user.cpp:47:25: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d",&n); ^ user.cpp:49:29: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d",&x); ^