Description: In the game of DotA, Pudge’s meat hook is actually the most horrible thing for most of the heroes. The hook is made up of several consecutive metallic sticks which are of the same length. Now Pudge wants to do some operations on the hook…

描述 In the game of DotA, Pudge’s meat hook is actually the most horrible thing for most of the heroes. The hook is made up of several consecutive metallic sticks which are of the same length. Now Pudge wants to do some operations on the hook. Let us n…

Just a Hook In the game of DotA, Pudge’s meat hook is actually the most horrible thing for most of the heroes. The hook is made up of several consecutive metallic sticks which are of the same length. Now Pudge wants to do some operations on the hook.…

学习线段树第二天,这道题属于第二简单的线段树,第一简单是单点更新,这个属于区间更新. 区间更新就是lazy思想,我来按照自己浅薄的理解谈谈lazy思想: 就是在数据结构中,树形结构可以线性存储(线性表)也可以树状存储(链表) 树形typedef struct node { int data; struct node* Lchild; struct node* Rchild; }Btree,*BTree;BTree = (BTree)malloc(Btree);好像是这样吧...大半个暑假过去忘得…

http://acm.hdu.edu.cn/showproblem.php?pid=1698 n个数初始每个数的价值为1,接下来有m个更新,每次x,y,z 把x,y区间的数的价值更新为z(1<=z<=3),问更新完后的总价值. 线段树的区间更新,需要用到延迟标记,简单来说就是每次更新的时候不要更新到底,用延迟标记使得更新延迟到下次需要更新或者询问的时候. 这题只需要输出总区间的信息,即直接输出1结点的信息. #include <iostream> #include <cstd…

题解: 和hdu1166敌兵布阵不同的是 这道题需要区间更新(成段更新). 单点更新不用说了比较简单,区间更新的话,如果每次都更新到底的话,有点费时间. 这里就体现了线段树的另一个重要思想:延迟标记. 在定义树节点结构体的时候加一个标记:flag. typedef struct node { node():l(0),r(0),data(0),flag(0){} //构造函数 初始化数据成员 int l,r; int data; //每个节点的数据 int flag; //延迟标记 }TNode;…

Problem Description In the game of DotA, Pudge’s meat hook is actually the most horrible thing for most of the heroes. The hook is made up of several consecutive metallic sticks which are of the same length. Now Pudge wants to do some operations on t…

来谈谈自己对延迟标记(lazy标记)的理解吧. lazy标记的主要作用是尽可能的降低时间复杂度. 这样说吧. 如果你不用lazy标记,那么你对于一个区间更新的话是要对其所有的子区间都更新一次,但如果用lazy标记的话. 就只需要更新这一个区间然后加一个标记,那么如果要访问这个区间的子区间,因为有lazy标记,所以下次访问会将区间的lazy标记传递给子区间,让后去更新子区间,这样我们不必在每次区间更新操作的时候更新该区间的全部子区间,等下次查询到这个区间的时候只需要传递lazy标记就可以了 但从时…

Just a Hook Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 22730    Accepted Submission(s): 11366 Problem Description In the game of DotA, Pudge's meat hook is actually the most horrible thing…

Just a Hook Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 17124    Accepted Submission(s): 8547 Problem Description In the game of DotA, Pudge’s meat hook is actually the most horrible thing f…