const size_t N = 10050;
int heap[N];
//size_t cnt = 0;
#define cnt (*heap)

//percolate up
/**
* Insert item x,allowing duplicates.
*/
void push(int x){
    if (cnt == N - 1) return; // 堆已满
    size_t hole = ++cnt;
    while(hole != 1 && heap[hole>>1] >= x){
        heap[hole] = heap[hole>>1];
        hole >>= 1;
    }
    //hole==1||heap[hole>>1]<x
    heap[hole]=x;
}

//precolate down
/**
* Internal method to percolate down in the heap.
* hole is the index at which the percolate begins.
*/
void percolate_down(size_t hole){
    int tmp = heap[hole], child;
    while((child = hole << 1) <= cnt){  //hole位置 至少有left child
        if(child != cnt && heap[child] > heap[child+1]) ++child;
        if(heap[child] < tmp){
            heap[hole] = heap[child];
            hole = child;
        } else break;
    }
    heap[hole] = tmp;
}

void pop(){
    if(cnt == 0) return;
    heap[1] = heap[cnt--];
    percolate_down(1);
}

void build_heap(){
    for(int i = cnt >> 1; i; --i){
        percolate_down(i);
    }
}

size_t size(){
    return cnt;
}
#undef cnt