实现2d范围树c ++ [英] implement 2d range tree c++

问题描述

有人可以用一个实现来解释这个问题，因为我想使用它来解决2D RMQ，我知道段树，我的老师告诉我范围树是类似于2d段树，但我只是不能认为如何空间复杂度可以小于n ^ 2像2d段树。

我不知道这是什么，但它是真的，它像合并排序，所以内存将小于n ^ 2使用向量

  void merge（vector< int>& res，vector< int>& a，vector< int& b $ b {
 int la = 0; 
 int lb = 0; 
 int sa = SIZE（a）; 
 int sb = SIZE（b）; 
 while（la  {
 if（la> = sa）{res.pb（b [lb]）; lb ++;} 
 else if（lb> = sb）{res.pb（a [la]）; la ++;} 
 else 
 {
 if ]）{res.pb（a [la]）; la ++;} 
 else {res.pb（b [lb]）; lb ++;} 
} 
} 
} 
 
 void build（int n，int l，int r）
 {
 if（l == r）
 {
 rtree [n]。 pb（ar [1]）; 
 return; 
} 
 int m =（l + r）/ 2; 
 build（2 * n，l，m）; 
 build（2 * n + 1，m + 1，r） 
 merge（rtree [n]，rtree [2 * n]，rtree [2 * n + 1]）;感谢：）

 
 
 
 
例如 org / wiki / Range_treerel =nofollow>维基百科，我在Google上发现的几个我之前的讲座，以及堆栈问题？
 
 
 
我没有在大学学习的乐趣，但它似乎是一个有趣的数据结构。
 
I have been trying to understand range tree for some time, but i still can't understand it.

Can someone explain it to me with an implementation, because i want to use it to solve 2D RMQ, i know segment tree, and my teacher tell me range tree is similar to 2d segment tree, but i just can't think how the space complexity can be less than n^2 like 2d segment tree.

I'm not sure about this, but is it true that, it's like merge sort, so the memory will be less than n^2 using vector
void merge(vector<int> &res,vector<int> &a,vector<int> &b)
{
    int la = 0;
    int lb = 0;
    int sa = SIZE(a);
    int sb = SIZE(b);
    while(la < sa || lb < sb)
    {
        if (la >= sa) {res.pb(b[lb]);lb++;}
        else if (lb >= sb) {res.pb(a[la]);la++;}
        else
        {
            if (a[la] < b[lb]) {res.pb(a[la]);la++;}
            else {res.pb(b[lb]);lb++;}
        }
    }
}

void build(int n,int l,int r)
{
    if (l == r)
    {
        rtree[n].pb(ar[l]);
        return;
    }
    int m = (l+r)/2;
    build(2*n,l,m);
    build(2*n+1,m+1,r);
    merge(rtree[n],rtree[2*n],rtree[2*n+1]);
}
Thanks :)
解决方案
Have you checked the usual cookie jars?

Such as Wikipedia, a former lecture of several I found on Google and in addition to a Stack Question?

I did not have the pleasure of learning it at University but it appears to be an interesting data structure.

                        
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