zoukankan      html  css  js  c++  java
  • 线段树模板(区间和最大值最下值)

    //===========================================
    //segment tree
    //final version
    //by kevin_samuel(fenice)苏州大学孙俊彦
    #include <iostream>
    #include <cstdio>
    #include <cmath>
    
    
    using namespace std;
    
    #define MAXN 100
    #define INF 0x3fffffff
    
    int A[MAXN];
    //int max;
    //int min;
    
    struct node
    {
        int left;
        int right;
        int max;           //维护最大值
        int sum;          //维护区间和
        int min;           //维护最小值
    }Tree[MAXN<<2];
    
    
    void maintain(int root)         //向上调整
    {
        int LC = root<<1;
        int RC = (root<<1)+1;
        Tree[root].sum = Tree[LC].sum + Tree[RC].sum;
        Tree[root].max = max(Tree[LC].max,Tree[RC].max);
        Tree[root].min = min(Tree[LC].min,Tree[RC].min);
    }
    
    void Build(int root,int start,int end)                     //构建线段树
    {
        Tree[root].left = start;
        Tree[root].right = end;
        if(start == end)
        {
            Tree[root].sum = A[start];
            Tree[root].max = A[start];
            Tree[root].min = A[start];
            return;
        }
        int mid = (start + end)>>1;
        Build(root<<1,start,mid);
        Build((root<<1)+1,mid+1,end);
        maintain(root);
    }
    
    void update(int root,int pos,int value)                     //更新点的值
    {
        if(Tree[root].left == Tree[root].right && Tree[root].left == pos)
        {
            Tree[root].sum += value;
            Tree[root].max += value;
            Tree[root].min += value;
            return;
        }
        int mid = (Tree[root].left + Tree[root].right)>>1;
        if(pos <= mid)
            update(root<<1,pos,value);
        else
            update((root<<1)+1,pos,value);
        maintain(root);
    }
    
    int Query(int root,int start,int end)                         //查询区间和
    {
        if(start == Tree[root].left && Tree[root].right == end)
        {
            return Tree[root].sum;
        }
        int mid = (Tree[root].left + Tree[root].right)>>1;
        int ret = 0;
        if(end <= mid)
            ret += Query(root<<1,start,end);
        else if(start >= mid+1)
            ret += Query((root<<1)+1,start,end);
        else
        {
            ret += Query(root<<1,start,mid);
            ret += Query((root<<1)+1,mid+1,end);
        }
        return ret;
    }
    
    int RminQ(int root,int start,int end)              //查询区间最小值
    {
        if(start == Tree[root].left && Tree[root].right == end)
        {
            return Tree[root].min;
        }
        int mid = (Tree[root].left + Tree[root].right)>>1;
        int ret = INF;
        if(end <= mid)
            ret = min(ret,RminQ(root<<1,start,end));
        else if(start >= mid+1)
            ret = min(ret,RminQ((root<<1)+1,start,end));
        else
        {
            int a = RminQ(root<<1,start,mid);
            int b = RminQ((root<<1)+1,mid+1,end);
            ret = min(a,b);
        }
        return ret;
    }
    
    int RmaxQ(int root,int start,int end)                 //查询区间最大值
    {
        if(start == Tree[root].left && Tree[root].right == end)
        {
            return Tree[root].max;
        }
        int mid = (Tree[root].left + Tree[root].right)>>1;
        int ret = 0;    //modify this
        if(end <= mid)
            ret = max(ret,RmaxQ(root<<1,start,end));
        else if(start >= mid+1)
            ret = max(ret,RmaxQ((root<<1)+1,start,end));
        else
        {
            int a = RmaxQ(root<<1,start,mid);
            int b = RmaxQ((root<<1)+1,mid+1,end);
            ret = max(a,b);
        }
        return ret;
    }
    
    int main()
    {
        return 0;
    }


  • 相关阅读:
    网络编程-TCP/IP各层介绍(5层模型讲解)
    TCP、UDP数据包大小的限制
    NAT(地址转换技术)详解(转载)
    用户访问网站基本流程及原理(转载)
    python网络编程相关
    python基础学习笔记——网络编程(协议篇)
    详解Python中的相对导入和绝对导入
    当列表推导式遇到lambda(匿名函数)
    python单例模式的几种实现方法
    用python将多个文档合成一个
  • 原文地址:https://www.cnblogs.com/riskyer/p/3246707.html
Copyright © 2011-2022 走看看