Compilare: main.cpp: In function 'int main()': main.cpp:26:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] fout<<l<<endl<<n-1<<endl;for(int i=0;i<w.size();i++){fout<<w[i].first<<' '<<w[i].second<<endl;} ~^~~~~~~~~ main.cpp:26:8: warning: 'l' may be used uninitialized in this function [-Wmaybe-uninitialized] fout<<l<<endl<<n-1<<endl;for(int i=0;i<w.size();i++){fout<<w[i].first<<' '<<w[i].second<<endl;} ^