2-线段树

class Tree
{
    struct Node
    {
        int start;
        int end;
        int value;
        Node(int _start,int _end, int _value) : start(_start), end(_end), value(_value){}
    }
    int listnum;
    int maxlistnum;
    Node *list;
public:
    ~Tree()
    {
        if(list)
        	delete[] list;
    }
    Tree(int* _list,int _listnum) : listnum(_listnum)
    {
        int num = 1;
        while(true)
        {
            if(num<listnum)
            {
                num+=2;
                continue;
            }
            else
            {
                break;
            }
        }
        maxlistnum = num*2-1;
        list = new Node[maxlistnum];
        for(int i = num-1,j = 0;j<listnum;i++,j++)
        {
            list[i].value = _list[j];
        }
        build(0);
    }
private:
    Node build(int buildnum)
    {
        if(buildnum*2+2>maxlistnum-1)
        {
            list[buildnum].start = list[buildnum].end = buildnum+1;
            return list[buildnum];
        }
        
        Node NodeL = build(buildnum*2+1);
        Node NodeR = build(buildnum*2+2);
        list[buildnum].start = NodeL.start;
        list[buildnum].end = NodeR.end;
        list[buildnum].value = NodeL.value+NodeR.value;
        return list[buildnum];
    }
}

class Tree
{
    int listnum;
    int maxlistnum;
    Node *list;
public:
    int query(int start,int end,int nodenum)
    {
        if(start<=_start && end>=_end)
            return list[]
    }
}