class big_heap_int{
private:
vector<int>heap;
void down(int x){
int s=x*2;
while(x<heap.size()-1){
if(heap[s]<heap[s+1]){
++s;
}
if(heap[x]<heap[s]){
swap(heap[x],heap[s]);
x=s,s=2*x;
}
else
break;
}
}
void up(int x){
while(x>1){
int fa=x/2;
if(heap[x]>heap[fa]){
swap(heap[x],heap[fa]);
x=fa;
}else{
break;
}
}
}
public:
big_heap_int(){heap.push_back(0);};
~big_heap_int(){};
void push(int x){
heap.push_back(x);
up(heap.size()-1);
}
void pop(){
heap[1]=*(heap.end()-1);
heap.pop_back();
down(1);
}
int top(){
return heap[1];
}
};
