combinations

问题 Say I have a range of number, say {2,3,4,5}, stored in this order in a std::vector v , and that I want to list all possibles subsets which end with 5 using STL... that is : 2 3 4 5 2 3 5 2 4 5 3 4 5 2 5 3 5 4 5 5 ( I hope i don't forget any:) ) I tried using while(next_permutation(v.begin(),v.end())) but didn't come up with the wanted result :) Does anyone have an idea? PS : those who have done the archives of google code jam 2010 may recognize this :) 回答1: tomasz describes a solution which

问题 I hope I don't butcher the explanation of my question: I've got a table that has hundreds of rows, each row is a recipe with nutritional information, for example: recipe_table: id | calories | protein| carbs | fat recipe1, 100, 20g, 10g, 2g recipe2, 110, 10g, 12g, 12g recipe3, 240, 20g, 1g, 23g .... I needed to create a new table (recipe_index) that would show every possible combination of every recipe in recipe_table as a set of 3, so it would look something like: recipe_index: id1 | id2 |

问题 What I want to achieve is to generate combinations in different processes to get them faster. In this post there'a a method to get the kth combination of a set of n numbers in groups of p numbers. Once I have the kth combination, I can manage to generate the rest of combinations in different processes (dividing the total number of combinations between processes so I know the combination each process has to begin with). The way I've done this has been with the same function that gets the kth

问题 I am new to coding and R and would like your help. For my analysis, I am trying to run regression on a time series data with 1 dependent variable (Y) and 4 Independent Variables (X1, X2, X3, X4). All these variables (Y and X) have 4 different transformations (For example for X1 - X1, SQRT(X1), Square(X1) and Ln(X1)). I want to run the regressions for all the possible combinations of Y (Y, SQRT(Y), Square(Y), Ln(Y)) and all the combinations of X values so that in the end I can decide by

问题 I have several arrays in VB.net. These arrays have different lengths and I need the combination between them. The simple solution is using nested loop as in the example: Dim Array1= {10, 11, 12} Dim Array2= {15} Dim Array3= {1,2,3} Dim array(2) As Object array(0) = Array1 array(1) = Array2 array(2) = Array3 for (a = 1 to < Array1.Length - 1) for (b = 1 to < Array2.Length - 1) for (c = 1 to < Array3.Length - 1) 'Get combination Next Next Next Output: {10,15,1},{10,15,2},{10,15,3},{11,15,1},{11

问题 I would like to generate combinations with length 9 out of a sorted list (length 150) without any repeated values: 24, 110, 157, 256, 278, 368, 416, 502, 593, 666, 751, 801, 827, 925, 991, 1044, 1118, 1159, 1203, 1296, 1375, 1479, 1546, 1621, 1679, 1695, 1726, 1832, 1922, 1978, 1995, 2041, 2119, 2160, 2240, 2315, 2421, 2493, 2527, 2543, 2559, 2654, 2762, 2813, 2883, 2950, 2982, 3009, 3052, 3103, 3162, 3239, 3346, 3427, 3462, 3480, 3548, 3638, 3670, 3761, 3833, 3898, 3946, 3979, 4051, 4096,

问题 I am searching an algorithm which gives me the next permutation with a specific strength. A permutation of length n is defined with the elements (1,2,3,...n) What is the strength of a permutation? The strength of a permutation with length 10 is definded as |a1-a2|+|a2-a3|+...+|a9-a10|+|a10-a1| . For example: (1,2,3,4,5,6) has the strength 10 (1,2,6,3,4,5) has the strength 14 Exist there a formula to compute the next permutation of a given strength and length, or its necesary to compute all

问题 Say I have an array [10000,5000,1000,1000] and I would like to find the closest sum of numbers to a given number. Sorry for the bad explanation but here's an example: Say I have an array [10000,5000,1000,1000] I want to find the closest numbers to, say 6000 . Then the method should return 5000 and 1000 another example : we want the closest to 14000 , so then he should return 10000 and 5000 here i've tried on php but it's something wrong when i put 6000 i should get 5000 and 1000 <?php $arr =

问题 This one is baking my noodle big time! I have some arrays inside an array that looks like this var lidHours = {"192611":[ ["07:00","21:30"], ["07:00","21:30"], ["07:00","21:30"], ["09:00","21:30"], ["09:00","00:00"], ["08:00","08:00"], ["",""] ] } And an array of the week days var weekDays = new Array("Mon", "Tue", "Wed", "Thur", "Fri", "Sat", "Sun"); So each array represents a day of the week. I'm outputting onto the page like this: Monday: 7:00 - 21:00 and so on... But you can see that the

问题 I trying to figure out a way to get a list of product combinations with unique users in R. This is a follow up question to [Generate matrix of unique user-item cross-product combinations df <- data.frame(Products=c('Product a', 'Product b', 'Product a', 'Product c', 'Product b', 'Product c', 'Product d'), Users=c('user1', 'user1', 'user2', 'user1', 'user2','user3', 'user1')) Output of df is: Products Users 1 Product a user1 2 Product b user1 3 Product a user2 4 Product c user1 5 Product b