Compilare: user.cpp: In function ‘void bfs(int)’: user.cpp:16:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<grf[*dq.begin()].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:30:24: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d",&n); ^ user.cpp:32:33: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d%d",&a,&b); ^