I’m quiet new in Java data manipulation so I need some help if someone have a some good tips. Actually, I want just to find a easy way to sort a 2D list. I create a list like this: And then I want to have a result sorted by the second element like: I tried something like Arrays.sort(A.toArray(), (int[]a, int[]b)
Tag: sorting
Java sorting list of array vs sorting list of list
I have a list of points where each point is a tiny list of size 2. I want to sort the list of points in increasing order of x and if x values are equal, I break tie by sorting in decreasing order of y. I wrote a custom comparator to sort the points like this: Here’s the input before
Rearrange substrings using two criteria [closed]
Closed. This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 12 months ago. Improve this question Given a String: I need to sort its substrings first by numbers (in descending order) and then by letters, so
Sort int[] array
I’m a bit confused on how to sort this array using the following conditions: int[] array = { 3, 15, 7, 11, 6, 4, 1, 8, 10, 13 }; The conditions are as follows: The largest integer is first The second-largest integer is last The third-largest integer should be second The pattern continues, leaving the smallest number in the middle.
Index 16 out of bounds for length 16
I am trying to sort an array of x elements using quickSort but I am getting an error “Index 16 out of bounds for length 16” please help. Answer For an array of 16 elements the indexes are 0 to 15. Thus index 16 is not part of the array and you get the OutOfBoundsException.
How to Sort List based on Inner Object’s property in java 8
I have classes structure similar to: I have two different tables Source and Target, and after joining them I am getting four columns in the query output. I am constructing Response object using values of these four columns. I have data in Response object with these 4 properties sourceId, sourceName, targetId, targetName. I can have sourceId, sourceName same on the
Sort character array using java comparator
Sort a character array lexicographically with an additional condition that all c’s comes before all b’s. This could be done manually but I want to code it via inbuilt sorting using comparators. The code I wrote – Gives output: [a, a, a, a, a, b, c, b, d, r, r]. The c only comes before one of the b’s. If
arranging the records in customised way
Sort Procedure First sort by the delivered date & in case of multiple records on same date sort by delivered time (Note: if a record has both ordered and Delivered Date ,it should be sorted by Delivered date only) 08-JUN: 03.00, 08-JUN: 04.00 Then look at the ordered date without delivered date which also exists for 08-JUN & sort by
Java Quick Sort Performance
I was doing sorting array problems and found one of the quick sorting solution extremely fast, and the only difference is the two lines of code in function 1Partition. Wondering why the following two lines of code in 1Partition can greatly improve the performance: Here’s the full source code: } Answer I guess you are doing the question on a
Difference between addChildEventListener, addValueEventListener, and addOnCompleteListener when using orderByChild()?
I’m trying to sort and display data from Firebase using orderByChild() and used: I kept on wondering why it’s not sorting until I realized that childEventListener was used in the documentation. It should’ve been: What is the difference between the two and addValueEventListener when it comes to using orderByChild or any sorting method? Does get() not follow orderByChild()? Answer All