Compilare: main.cpp:5:95: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type] 5 | __gnu_cxx::rope<int> v[300009];std::ifstream w("stramosi.in");std::ofstream e("stramosi.out");main(){int n,m,x,q; w>>n>>m;for(q=1;q<=n;q++){w>>x;v[q]=v[x]+q;}while(m--){w>>x>>q;e<<(b>q?l[b-q-1]:0)<<'\n';}} | ^~~~ main.cpp: In function 'int main()': main.cpp:5:183: warning: comparison of integer expressions of different signedness: '__gnu_cxx::rope<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare] 5 | __gnu_cxx::rope<int> v[300009];std::ifstream w("stramosi.in");std::ofstream e("stramosi.out");main(){int n,m,x,q; w>>n>>m;for(q=1;q<=n;q++){w>>x;v[q]=v[x]+q;}while(m--){w>>x>>q;e<<(b>q?l[b-q-1]:0)<<'\n';}} | ^