Compilare: main.cpp: In function 'int bfs(int, int)': main.cpp:28:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<L[nod].size();i++){ ~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:53:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=0;j<L[i].size();++j){ ~^~~~~~~~~~~~ main.cpp:44:30: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d%d",&n,&m); ^ main.cpp:47:34: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d%d",&x,&y); ^