Compilare: main.cpp:3:73: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type] using namespace std;ifstream f("vila2.in");ofstream g("vila2.out");main(){int N,K;f>>N>>K;K++;vector<int>V(N);for(auto &i:V)f>>i;deque<int>P(1,0),Q(1,0);int R=0;for(int i=1;i<N;i++){if(i>=K){U(P)U(Q)}while(!P.empty()&&V[i]>V[P.back()])P.pop_back();P.push_back(i);while(!Q.empty()&&V[i]<V[Q.back()])Q.pop_back();Q.push_back(i);R=max(R,V[P.front()]-V[Q.front()]);}g<<R;} ^