Algorithm --分治法 分治法 一、基本概念 分治策略是:对于一个规模为n的问题,若该问题可以容易地解决(比如说规模n较小)则直接解决,否则将其分解为k个规模较小的子问题,这些子问题互相独立且与原问题形式相同,递归地解这些子问题,然后将各子问题的解合并得到原问题的解。这种算法设计策略叫做分治法。 任何一个可以用计算机求解的问题所需的计算
我们用伪代码来具体分析~ Divide-and-Conquer(P) 1. if |P|≤n0 2. then return(ADHOC(P)) 3. 将P分解为较小的子问题 P1 ,P2 ,…,Pk 4. for i←1 to k 5. do yi ← Divide-and-Conquer(Pi) △ 递归解决Pi 6. T ← MERGE(y1,y2,…,yk) △ 合并子问题 7. return(T) 其中|P|表示...
1.分治(Divide-and-Conquer(P))算法设计模式如下: if |P| <=n0 then return(ADHOC(P)) //将P分解为较小的子问题 P1,P2,……,Pk for i<-1 to k do yi <- Divied-and-Conquer(Pi) 递归解决Pi T <- MERGE(y1,y2,……,yk)合并子问题 return(T) 其中|P| 表示问题P的规模,n0为(阈值),表...
(2005). A Divide-and-Conquer Discretization Algorithm. Lecture Notes in Computer Science. No. 3613. P. 1277-1286.Min, F., Xie, L., Liu, Q., Cai, H.: A Divide-and-Conquer Discretization Algorithm. In: Wang, L., Jin, Y. (eds.) FSKD 2005. LNCS (LNAI), vol. 3613, pp. ...
4.Give a divide and conquer algorithm for the following problem: you are given two sorted lists of sizemandn, and are allowed unit time access to theith element of each list. Give anO(lg m + lgn)time algorithm for computing thekth largest element in the union of the two lists. (For...
1 : -1; } int divideConquer(int x, int y, int n) { int s = sign(x) * sign(y); // 正负号 x = abs(x); y = abs(y); if(x == 0 || y == 0) return 0; else if(n == 1) return s * x * y; else { int A = (int) x / pow(10, (int)(n / 2)); int ...
Divide-and-conquer algorithms: The divide-and-conquer algorithm is an effective algorithm that works by recursively breaking down a problem into two or more subproblems of the same or related type until these become simple enough to be solved directly and rather easily. ...
Schilling. A practical divide-and-conquer algorithm for the rectangle intersection problem. Information Sciences, 42(2):95-112, July 1987.R.H. Guting and W. Schilling, "A Practical Divide-and-Conquer Algorithm for the Rectangle Intersection Problem," Information Sciences, vol. 42, no. 2, pp...
#include<iostream>#include<cmath>using namespace std;intsign(int x){returnx>0?1:-1;}intdivideConquer(int x,int y,int n){int s=sign(x)*sign(y);// 正负号x=abs(x);y=abs(y);if(x==0||y==0)return0;elseif(n==1)returns*x*y;else{intA=(int)x/pow(10,(int)(n/2));int...
下面是从算法导论(Introduction to Algorithm Edition 3)上copy下的一小段话,解释的相当清楚。 Recurrences go hand in hand with the divide-and-conquer paradigm, because theygive us a natural way to characterize the running times of divide-and-conquer algorithms.A recurrence is an equation or inequalit...