一种最坏情况线性运行时间的选择算法 - The missing worst-case linear-time Select algorithm in CLRS. 选择算法也就是求一个无序数组中第K大(小)的元素的值的算法,同通常的Top K等算法密切相关. 在CLRS中提到了一种最坏情况线性运行时间的选择算法,在书中给出了如下的文字描述(没有直接给出伪代码). 1.Divide n elements into groups of 5 2.Find median of each group (Ho…
算法导论(CLRS)答案 Chapter Section I 1 2 p II 1 2 3 p III 1 2 p IV 1 2 3 4 p V 1 2 3 4 p VI 1 2 3 4 5 p VII 1 2 3 4 p VIII 1 2 3 4 p IX 1 2 3 p XII 1 2 3 XIII 1 2 3 4 p 假设你有兴趣,能够选一个章节去完毕. 欢迎watch/fork/star/contribute我的项目. 欢迎挑错. Follow @louis1992 on github…
本文是一篇笔记,大部分内容取自 CLRS 第三版,第 24.1 节. Exercise 24.1-4 Modify the Bellman-Ford algorithm so that it sets $v.d$ to $-\infty$ for all vertices $v$ for which there is a negative-weight cycle on some path from the source to $v$. Theorem 24.4 (Correctness of…
Bridging signals Time Limit: 1000MS Memory Limit: 10000K Total Submissions: 12251 Accepted: 6687 Description 'Oh no, they've done it again', cries the chief designer at the Waferland chip factory. Once more the routing designers have screwed up c…
//maximum and minimum 暴力遍历 O(n) //i-th element dicide and conquer random_selected_partition k(all the element samller than value[k] put left of value[k],all tht elenment larger than value[k] put right) recurrence test if(i=k)return value[k] i…
//intput array A,output array result. count array count . //all the elements is in te range of 0~k. //if k=O(n),the complexity is Θ(n) //counting sort is stable for(i=0;i<n;i++)result[i]=0; for(i=1;i<=n;i++)count[a[i]]++; for(i=1;i<=n;i++)count…
//max_heap heap_maximum:return A[1] O(1); Extract_Heap_maximum:swap(A[1],A[heap.size]) adjust up to down from A[1] to hold the max_heap character O(lgn) every stepfind max child increase_Heap_max(i,key):[key>=A[i]],adjust down to up from A[…
//the first k elements interviewed and rejected, //for the latter n-k elements ,if value >max,return value, else return n'elements. #include<stdio.h>#include<stdlib.h>#include<time.h>#define ARRAY_SIZE 1000#define RANDOM_SIZE 100int…
T(n)=aT(n/b)+f(n); where we can interpret n/b to mean either floor(b/n) or ceil(b/n), Then T (n) has the following asymptotic bounds: 1. If f (n)= O(nlogb a-c) for some constant c> 0, then T (n)=Θ(nlogb a)2.If f (n)= Θ(nlogb a), then T (n)=Θ(nlogb a…
O(n^2)过不了.必须要用一个额外的数组保存当前长度最小值,然后lgn查表 AC代码 #include<cstdio> #include<algorithm> using namespace std; const int maxn=100000+5; const int INF=1<<30; int dp[maxn],a[maxn],ans[maxn]; int main(){ int T,n; scanf("%d",&T); while(…
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 20404 Accepted Submission(s): 12231 Problem Description The inversion number of a given number sequence a1, a2, -, an is the number of pairs (ai, aj…
Almost Sorted Array Time Limit: 4000/2000 MS (Java/Others) Memory Limit: 262144/262144 K (Java/Others)Total Submission(s): 10562 Accepted Submission(s): 2449 Problem Description We are all familiar with sorting algorithms: quick sort, merge sor…
# 题目 1. Two Sum Given an array of integers, return indices of the two numbers such that they add up to a specific target. You may assume that each input would have exactly one solution. Example: , , , ], target = , Because nums[] + nums[] = + = , , ]…
