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 H********e发帖数: 130 1来自主题: JobHunting版 - 请教leetcode Subsets II我也贴一个我做的，大数据测试60ms 我的写了一个子函数，可以生成 大小为m的 subset，subset不会因为duplicate element重复，然后主函数循环调用子函数 class Solution { public: vector > subsetsWithDup(vector &S) { // Start typing your C/C++ solution below // DO NOT write int main() function vector > subsets; if(S.size()==0) return subsets; sort(S.begin(),S.end()); int len=S.size(); int * a=new int[len]; for(int i=0;i a[... 阅读全帖
 l*****n发帖数: 52 2来自主题: JobHunting版 - 请教一下subset I 输出子集顺序问题leetcode subset 我用eclipse调试 import java.util.*; public class subSets { public static HashSet> subsets(int[] s){ HashSet> result = new HashSet >(); if(s.length == 0|| s== null) return null; //Arrays.sort(s); ArrayList list = new ArrayList(); recursion(result,list,s,0); return result; } public static void recursion(HashSet> result, Array... 阅读全帖
 x*******5发帖数: 152 3来自主题: JobHunting版 - Subset of size m Problem请教各位大牛一个问题： Problem: Output all subsets of size of m from an array Solution Hints: String permutation Problem variant Python Codes: def Subset_m(v,l,m,output): "Find all subsets of an array v of size m, need fixing" if l==m: print output return for i in range(l,len(v)): output[l]=v[i] Subset_m(v,l+1,m,output) C++ Codes: /*Description: output all the subset of size m Input:vector v, int m,int l, vector& output Output: void */ ... 阅读全帖
 f*********m发帖数: 726 4来自主题: JobHunting版 - 请教leetcode Subsets II碰上类似的问题，除了用set,总是搞不定。谢谢指教。要排序和用prev吗？ Given a collection of integers that might contain duplicates, S, return all possible subsets. Note: Elements in a subset must be in non-descending order. The solution set must not contain duplicate subsets. For example, If S = [1,2,2], a solution is: [ [2], [1], [1,2,2], [2,2], [1,2], [] ]
 R******1发帖数: 58 5来自主题: JobHunting版 - 请教leetcode Subsets II刚写了一个可以work的，但是感觉效率很低 还是实现了一个find的function class Solution { public: vector > subsetsWithDup(vector &S) { vector myset = S; sort (myset.begin(), myset.end()); return subset (myset); } vector< vector > subset (vector &S) { vector < vector > res; vector < vector > imediate; vector < vector >::iterator it; vector temp; int lastdigit, pre; if (S.size() == 1... 阅读全帖
 s*******2发帖数: 791 6来自主题: Statistics版 - Help for freq subsetI use first. and last. in data step. It works well. I will try sql later. proc sort data=raw; by personid; run; data subset (drop=count); set raw; by personid; if first.personid then count=1; else count+1; if count<=3 then output; proc print data=subset; title 'Subset size is 3'; run;
 r********0发帖数: 65 7来自主题: Statistics版 - [R]how to sample all possible continuous subset from ordered datarow <- seq(1:100) row <- sample(row) ## it will randomize the 100 numbers then you can pick like first n numbers(depends on the size of each subset you need) as your subset index. c <- row[1:n] data[c,] if you want all the possible sizes of subset i'm afraid you still need to use loop. Hope it might help you
 r*******y发帖数: 1081 8来自主题: JobHunting版 - subsetgivn m sets. some sets may be subsets of others. If one set is a subset of another set, then this smaller set will be removed. Finally we have the sets from which we can not remove any set. Assume the elements in all the sets are same type and only "==" operator is supported on these elements. Is there any good algorithm to do this job ? Thanks.
 x*******5发帖数: 152 9来自主题: JobHunting版 - Subset of size m Problem没有办法了，只能上这个了 def Subset_m(v,l,m,result): "Find all subsets of an array v of size m, need fixing" if l==m: if sorted(v[:m]) not in result: print v[:m] result.append(sorted(v[:m])) return for i in range(l,len(v)): v[l],v[i]=v[i],v[l] Subset_m(v,l+1,m,result) v[l],v[i]=v[i],v[l] Test: v=[1,2,3] Output: [1, 2] [1, 3] [2, 3] 这个应该对的了，用东西记录已经存在的subset(因为是set，所以要sorted存储)
 e*******8发帖数: 94 10题目在此: http://stackoverflow.com/questions/12278528/find-subset-with-el 解法： http://algnotes.wordpress.com/2012/09/20/find-subset-with-eleme 没想明白照什么顺序解决O(nk)个subproblems才能有O(nk)的时间复杂度？
 b*****i发帖数: 130 11来自主题: JobHunting版 - 请问一个java的问题(leetcode subsets一题）我是按照这位大侠的解法来做leetcode subsets这题的。 http://blog.csdn.net/u011095253/article/details/9158397 01.public class Solution { 02. public ArrayList> subsets(int[] S) { 03. ArrayList> res = new ArrayList Integer>>(); 04. ArrayList tmp = new ArrayList(); 05. Arrays.sort(S); 06. res.add(tmp); 07. dfs(res,tmp,S,0); 08. return res; 09. } 10. 11. public void dfs(ArrayList阅读全帖
 a***e发帖数: 413 12来自主题: JobHunting版 - Leetcode上subsets-ii的疑问为什么要j>=prevSize？总是不理解这一点，多谢！ if (i==0||S[i]!=S[i-1]||j>=prevSize) https://oj.leetcode.com/problems/subsets-ii/ Given a collection of integers that might contain duplicates, S, return all possible subsets. Note: vector > subsetsWithDup(vector &S) { vector> ret; int n = S.size(); if (n==0) return ret; sort(S.begin(),S.end()); ret.resize(1); int prevSize = 0; for (int i=0; i { ... 阅读全帖
 s*x发帖数: 3328 13来自主题: CS版 - 我的证明：P is a subset of NPyou have to show P is non-zero in order to show P is a proper subset of NP; it is already known that P is a subset of NP.
 s****s发帖数: 42 14来自主题: Java版 - How to write subset method?Two integer sets, how to write a subset method to check if one is the other's subset?
 D**u发帖数: 204 15来自主题: Quant版 - bounded subset in a planeIn the plane, find a bounded subset who is congruent to a proper subset of itself.
 D**u发帖数: 204 16来自主题: Quant版 - bounded subset in a planeIn the plane, find a bounded subset who is congruent to a proper subset of itself.
 m**********u发帖数: 2 17来自主题: Statistics版 - Help for freq subsetI am using SAS to deal with a huge data file with over 10 millions of observations. “personid” is a variable. The structure of “personid” is like, for example, xxxx2, xxxx2, xxxx2, xxxx3, xxx3, xxxx5, xxxx5, xxxx5, xxxx6, xxxx7……., for a unique “personid”, there are several observations as shown in the example above. I am trying to get subset that the frequency of the unique “personid” has certain frequency, say, frequency=3, in the case of example above, that means I want to obtain a subset:
 l***a发帖数: 12410 18来自主题: Statistics版 - [R]how to sample all possible continuous subset from ordered dataif there is no duplicate and the order var has no missing, try this %macro subset; proc sql; select count(order) into :n from data0; quit; %do i=1 %to &n.; %do j=1 %to &n.-&i.+1; data data&i._&j.; set data0; if order>=&j. and order<=&n-&j+1; run; %end; %end; %mend subset; table?
 c******g发帖数: 63 19来自主题: Statistics版 - 请教linear regression中的subset selection算法小弟是新手。想请教一下关于linear regression中的subset selection，比如用leaps and bound选best subset，还有greedy的forward step-wise selection和backward step-wise selection这些算法，在哪本书或参考资料里有讲得详细一点的？（就是具 体的算法流程是怎样的，最好有点example） 像The Elements of Statistical Learning这本书对这些就是泛泛而讲，比如forward selection是从0个变量开始，一个一个加－－idea当然是这样，但具体地怎么操作呢？ 比如什么是挑选哪个新变量加入的metric呢（RSS？test error还是什么Mallow's Cp） ？什么是terminal condition表示不加了呢……这些都没讲…… 非常感谢！
 g**********y发帖数: 14569 20来自主题: JobHunting版 - subsetI am not sure what's your question. But as example, here is a simplified Java implementation, assume sets no more than 32. If more than that, you can use BigInteger or write your own class. public class Subset { public Set[] merge(Set[] sets) { HashMap cardinal = new HashMap(); HashMap map = new HashMap(); HashSet remove = new HashSet(); for (Set set : sets) { i... 阅读全帖
 i**********e发帖数: 1145 21来自主题: JobHunting版 - subset sum的问题这问题不简单，应该是 dp，这里有一个类似的解法，不过两个subset S1 和 S2 不局 限于拥有同样 n 个元素。 See "Balanced Partition" here: http://people.csail.mit.edu/bdean/6.046/dp/
 x*******5发帖数: 152 22来自主题: JobHunting版 - Subset of size m Problemdef Subset_m(v,l,m): "Find all subsets of an array v of size m, need fixing" if l==m: print v[:m] return for i in range(l,len(v)): v[l],v[i]=v[i],v[l] Subset_m(v,l+1,m) v[l],v[i]=v[i],v[l] Output: [1, 2] [1, 3] [2, 1] [2, 3] [3, 2] [3, 1] 感谢，现在正确了，其实就是string permutation的变体，谢谢
 f******p发帖数: 173 23我怎么觉得是O(n^3)呢 http://stackoverflow.com/questions/12278528/find-subset-with-el 里面ElKamina的答案是对的，不过有一处没说清楚,X[i,j] 应该是 the optimum result of selecting j elements from the first i elements provided that A[j-1 ] is included. 贴个代码 public int cal(int[] a, int k) { if (k <2 || a == null ||a.length < 2) return -1; Arrays.sort(a); if (k == 2) return a[a.length-1] -a[0]; int[][] res = new int[a.length + 1][a.length +1];... 阅读全帖
 s*****o发帖数: 1540 24来自主题: CS版 - 我的证明：P is a subset of NPNP when N =1 , NP = 1P = P therefore: NP contains P, 2P, 3P ... therefore: P is a subset of NP end.
 g*****i发帖数: 2162 25来自主题: Java版 - 请问Treeset/Treemap里面subSet(),subMap()的复杂度是多少?add remove delete都是O(logn) 那么求subSet()是O(logn)还是O(n)呢 ? 谢谢.
 j***3发帖数: 142 26来自主题: Programming版 - [Perl] how to create a new hash that is a subset of a exishow to create a new hash that is a subset of an existing hash? under some condition e.g. $key >=a and$key <=b. thanks
 f*******n发帖数: 1 27Steinman实验室的Science文章。非常老的一个抗原，很有意思的发现，非常新的认识 。这一期的Cell上有Akiko Iwasaki写的一篇prereview，记得这个版面有人评论过这个 日本mm是否美女来着，显然她的研究领域已经不仅仅是mucousal immunity了，应该还 会保持上升的。 http://www.sciencemag.org/cgi/content/abstract/315/5808/107 Science 5 January 2007: Vol. 315. no. 5808, pp. 107 - 111 DOI: 10.1126/science.1136080 Prev | Table of Contents | Next Reports Differential Antigen Processing by Dendritic Cell Subsets in Vivo Diana Dudziak,1 Alice O. Kamphorst,1 Gordon F. Heidkamp,1 Veit R. Buchholz,1 Christine Trump
 h*******d发帖数: 272 28来自主题: Statistics版 - 求教 full/reduce model+F test 与best subset procedure 的区别外行菜鸟学regression 混淆了很多概念请大家指点： 开始学了 共线性的危害；先检测FULL MODEL 根据t值剔除不显著的变量--reduced model 然后再用F-test CONFIRM. 后来又学了 best subset procedure（这里没再提共线性） 感觉2个都是减少变量，优化MODEL 的啊 区别在哪？ 谢谢大家 等待您的回复
 j***3发帖数: 142 29来自主题: Statistics版 - [R]how to sample all possible continuous subset from ordered dataif I have table like this: 1 1.234 2 1.657 3 1.564 4 2.343 .. ,, the first column is order information and the second column is value. is there a way to sample all possible continuous subset of x row from the table? thanks
 r********0发帖数: 65 30来自主题: Statistics版 - [R]how to sample all possible continuous subset from ordered dataHow to define your "continuous subset" here?
 D******n发帖数: 2836 31来自主题: Statistics版 - [R]how to sample all possible continuous subset from ordered datathats totally n(n+1)/2 subsets. table?
 j***3发帖数: 142 32来自主题: Statistics版 - [R]how to sample all possible continuous subset from ordered datamaybe I did not express myself clear enough, what I need is a subsets that has continuous row number, the solution rabbit1860 give is random row number. the solution libra give is in SAS ? the syntax looks strange to me. DaShagen, I think it is basically a sliding window of size x and step 1.
 y****t发帖数: 446 33来自主题: Statistics版 - 问一个data subset的问题我有两个datasets: first dataset: Name Response A * A * B * B * B * C * C * second dataset: Name Response A * A * A * B * C * C * C * D * D * E * 我想subset第二个dataset,让它只留下第一个dataset出现的name的数据，也就是把第 二个dataset里的D和E对应的observations都去掉 请教大家
 c*****m发帖数: 4817 34来自主题: Statistics版 - 问一个data subset的问题R >subset(b, match(b$name, a$name)>0)
 A*******s发帖数: 3942 35来自主题: Statistics版 - 请教linear regression中的subset selection算法Subset Selection in Regression这本书讲了不少细节，不过我觉得内容有点老。网上 有电子书。 简单来说GLM的automatic selection都是基于likelihood的，一般来说是likelihood ratio test with pre-specified significance level，当然也可以用AIC，BIC， cross validation之类的。 leaps forward
 D**o发帖数: 2653 36来自主题: Mathematics版 - 关于煙花不堪剪注意作者 \author{YHBKJ} Atiyah-Bott Localization 1 2012-09-05 09:24:19 \documentclass[a4paper,12pt]{article} \usepackage{amsfonts} \usepackage{amsmath,amsthm,amssymb} \usepackage{CJK,graphicx} \usepackage{amscd} \usepackage{amssymb} \newtheorem{theorem}{Theorem}[section] \newtheorem{corollary}{Corollary}[section] \newtheorem{definition}{Definition}[section] \newtheorem{lemma}{Lemma}[section] \begin{document} \title{\textbf{\Huge{Atiyah-Bott Localization 1}}}\author{YHBKJ}\date{}\ maketitle \begin{ab... 阅读全帖
 g*****k发帖数: 623 37来自主题: JobHunting版 - 问个算法题,修改版Why you people like to decrement m instead of incrementing m? By increment, you can get rid of push_back and erase, if you reserve size m for subset. Thus you can access subset[m] each time and don't need to erase elements. 题目的意思相当于有序打印集合A所有大小为3的子集，代码如下： void run(int a[], int n, int m, vector &subset) { if(n < m) return ; if(m == 0) { for(int i = 0; i < subset.size(); i++) cout << subset[i] << " "; cout << endl; return ; } subset.push_bac... 阅读全帖
 d*******l发帖数: 338 38来自主题: JobHunting版 - 问个算法题,修改版题目的意思相当于有序打印集合A所有大小为3的子集，代码如下： void run(int a[], int n, int m, vector &subset) { if(n < m) return ; if(m == 0) { for(int i = 0; i < subset.size(); i++) cout << subset[i] << " "; cout << endl; return ; } subset.push_back(a[0]); run(a+1, n-1, m-1, subset); vector::iterator it; subset.erase(subset.begin() + subset.size() - 1); run(a+1, n-1, m, subset); } int a[10] = {1,8,9,10,26}; int main() { vector v(0); ru... 阅读全帖
 z**********i发帖数: 88 39来自主题: Statistics版 - a R questionUsing SAS to subset data, I can get N=48, but using R, I can not, I don't know anything about. Would anybody check my R code and see where is the problem? Below is the SAS code and R code. Thanks. data x; set ALL_12222010; where tau>93 & abeta142<192 & PTAU181P>23;run; **n=48; #R code; sizing <- function(variable.name,dx.group){ cut.sample <- function(variable.name,dx.group){ attach(variable.name) variable.name\$enrich=as.numeric(tau>93 & abeta142<192 & PTAU181P>23); ... 阅读全帖
 g***s发帖数: 3811 40来自主题: JobHunting版 - 问个算法题2"In computer science, the subset sum problem is an important problem in complexity theory and cryptography. The problem is this: given a set of integers, does the sum of some non-empty subset equal exactly zero? For example, given the set { −7, −3, −2, 5, 8}, the answer is yes because the subset { −3, −2, 5} sums to zero. The problem is NP-complete. An equivalent problem is this: given a set of integers and an integer s, does any non-empty subset sum to s? Subset su... 阅读全帖
 n**********8发帖数: 188 41来自主题: JobHunting版 - Amazon interview question.(3)可以通过subset sum来证明这个问题是NP-hard： 给定一个subset sum的问题instance：f[1..n]和target_sum，我们可以通过调用avg_ partition的solution来解决这个instance in poly time。方法如下： 1）先假设f中有一个大小为m的subset加起来为target_sum（虽然我们并不知道m是多少 ，但我们可以enumerate m = 1..n） 2) 现在给定m，在f的基础上添加3个elements来构造一个新的数组g，然后我们可以证 明把avg_partition的solution在g上run一下，它能找出的解必然和f上subset sum的解 一一对应 2.1)首先加一个数x such that: target_sum/(m+1) 和(SUM(f[1..n])+x-target_sum) /(n-m+2) 一样大 2.2)其次再加2个数a和b，他们分别为a=10^10*(m+1) 和 b=10^10*(n-m+2)，这里10^ 10可以换成任何一个非常大或者非常小的数（这样导致它完全不和f里面的数在同... 阅读全帖
 d****n发帖数: 233 42来自主题: JobHunting版 - 问一到题目vector subsets(vector a) { int n = a.size(); // minimum negative sum int min = 0; // max postive sum int max = 0; for(int i = 0; i < n; i++) { if (a[i] < 0) { min += a[i]; } else { max += a[i]; } // mask[i] = 1 means there is a sub sum equals to i int mask[] = new int[-min + max + 1]; // lookupTable[i, j] = 1 means there is a sub sum equals to j // and a[i] is in the sub set ve... 阅读全帖
 c*****a发帖数: 808 43来自主题: JobHunting版 - PIE题: Phone number to words iterative 解法import java.util.Hashtable; public class Solution { Hashtable Dict = new Hashtable () ; public ArrayList letterCombinations(String digits) { ArrayList res = new ArrayList(); if(digits.length()==0){ res.add(""); return res; } Dict.put(2, new String[]{"a", "b", "c"}); Dict.put(3, new String[]{"d", "e", "f"}); Dict.put(4, new String[]{"g", "h", "i"}); ... 阅读全帖
 t****a发帖数: 1212 44来自主题: JobHunting版 - 这个题咋做？# Subset(k, n) = 1, if k == n # Subset(1, n) = n # Subset(k, n) = # Subset(k, n-1) + # Subset(k-1, n-1)
 T******n发帖数: 11 45来自主题: JobHunting版 - 问一个cracking code interview上的问题啊我用vector表示set，结果是一个vector的vector。不用recursion。 1. 把empty set加入结果； 2. 遍历set里的元素，每碰到一个都是把之前的结果复制一遍，然后把set里的新元素 加入，然后加入结果中； vector > powerSet(vector& set) { vector > subsets; vector emptySet; subsets.push_back(emptySet); for(int i = 0; i < set.size(); i++) { vector > add = subsets; for(int j = 0; j < add.size(); j++) { add[j].push_back(set[i]); subsets.push_back(add[j]); } } return subsets; }
 d****h发帖数: 21 46来自主题: JobHunting版 - 问一个cracking code interview上的问题啊初学者，给一个haskell解法： subsets :: [a] -> [[a]] subsets [] = [[]] subsets (x:xs) = (map (x:) (subsets xs))++(subsets xs)
 l**********1发帖数: 415 47Given two integers n and k, return all possible combinations of k numbers out of 1 ... n. For example, If n = 4 and k = 2, a solution is: [ [2,4], [3,4], [2,3], [1,2], [1,3], [1,4], ] the given api is public ArrayList> combine(int n, int k) the solution I got is as follows which is really slow O(n!) and time out at 10,7. So please provide any idea of higher efficiency algorithm for this one. Thanks in advance public void combination(ArrayList> r... 阅读全帖
 c*****a发帖数: 808 48来自主题: JobHunting版 - Combination Sum II哪里做错了大牛快来看看 Combination Sum II Given a collection of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T. Each number in C may only be used once in the combination. Note: All numbers (including target) will be positive integers. Elements in a combination (a1, a2, … , ak) must be in non-descending order. (ie, a1 ≤ a2 ≤ … ≤ ak). The solution set must not contain duplicate combinations. For example, given candidate set 10,1,2... 阅读全帖
 b********6发帖数: 35437 49来自主题: JobHunting版 - 这道facebook的题怎么解弄两个数组，A[n], B[n] where n is the number of jobs，然后再用一个变量来存总 cost，如果想把每一步的总cost和每一步的subset size存起来的话，也可以多弄几个 数组。 A[i] 存从0 - i个job的最优解subset的最后一个job的index B[i] 存A[i]对应的最优解subset的倒数第二个job的index 比如对于一个5个job的输入数组，A[4]=3，表示这5个输入的最优解subset的最后一个 job的index为3, 然后B[4]=2，表示取完3之后要去取2，然后找A[2]=1，然后找B[2]， 一路找一下去，时间复杂度是O(k)，k是subset的size
 Q***5发帖数: 994 50来自主题: Mathematics版 - 问measure的setwise convergenceI think you can prove (1) by the following arguments: 1.1 It is true when A is any open segment -- This is just by defination of cdf. 1.2 It is true for any open subset of [0 1]. An open subset is just a uninon of countably many opens segments. 1.3 It is true for any Borel measurable subset A: m_n(A) = inf_{A\subset D, D open}m_n(D)<= B\inf_{A\subset D, D open}m(D) = B m(A) measure
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