The tag has no wiki summary.

learn more… | top users | synonyms

0
votes
1answer
29 views

Design Pattern : Static Array/List in Class Object

I'm a CS alumni, but we didn't learn much by the way of OOP, or Design Patterns. I've heard the phrase C with iostreams and thought it fitting. Anyway that's besides the point. I am just curious about ...
-5
votes
0answers
34 views

Sorting a Difference-Array, URGENT help [on hold]

I have the following code. What it does is: There is an externally supplied input file which contains certain numbers. The numbers are first all sorted, and then all possible differences ( so always ...
4
votes
4answers
343 views

Why can't C arrays have 0 length?

The C11 standard says the arrays, both sized and variable length "shall have a value greater than zero." What is the justification for not allowing a length of 0? Especially for variable length ...
1
vote
2answers
55 views

A vector of pointers to different derived classes of the same base class

I am writing a game in C++ which has different enemy types. I have defined a base Enemy class and I also have derived classes enemy1, enemy2 etc. Now for updating these enemies in each iteration of ...
1
vote
5answers
146 views

What defines the dimensionality of an array?

I know that when we speak about an array having 1, 2, or 4 dimensions, we mean arrays like this: 1: [0] 2: [0,0] 3: [0,0,0] 4: [0,0,0,0] ... Is the first 'axis' of an array the only thing that ...
24
votes
11answers
7k views

How does the “Fourth Dimension” work with arrays?

Abstract: So, as I understand it (although I have a very limited understanding), there are three dimensions that we (usually) work with: The 1st could be represented by a line. The 2nd could be ...
2
votes
1answer
95 views

Improving the running time of Breadth First Search and Adjacency List creation

We are given an array of integers where all elements are between 0-9. have to start from the 1st position and reach end in minimum no of moves such that we can from an index i move 1 position back and ...
3
votes
2answers
180 views

Data structure for grid with negative indeces

Sorry if this is an insultingly obvious concept, but it's something I haven't done before and I've been unable to find any material discussing the best way to approach it. I'm wondering what's the ...
1
vote
1answer
107 views

How to construct a cubie representation of a rubik's cube, given an array

Just to get this out of the way, I have seen this, and it is not what I'm looking for. So, let's say you are programming a Rubik's Cube. (I know, very unoriginal, but bored programmers have to do ...
4
votes
4answers
518 views

Why do arrays in Java not override equals()?

I was working with a HashSet the other day, which has this written in the spec: [add()] adds the specified element e to this set if this set contains no element e2 such that (e==null ? e2==null : ...
2
votes
1answer
225 views

Why does Java support brackets behind variables and even behind method signatures? [closed]

Java allows this: class X{ int i,j[]; // j is an array, i is not } and even worse, it allows this: class X{ int foo(String bar)[][][] // foo actually returns int[][][] { return null; } ...
0
votes
0answers
32 views

Search substring using suffix array (and LCP)

I'm searching for a best way to improve suffix array run time using LCP. My text (about 2 500 000 chars) seems like: 0ricco0eric0america0polo0.... My thoughs: SA=suffixArray char=firstChar(input) s ...
5
votes
1answer
161 views

At ping, why do we have to do array copying instead of passing on the source array that the client sent to us?

So I have been googling about this OpenSSL heart-bleed thing and somehow sees that it is caused by the heartbeat extension which requires client to ping the server to show its aliveness and it all ...
2
votes
1answer
98 views

Accessing a private array when I have an extension method

I'm trying to make a number of data classes for my C#/XNA game, which would essentially be a wrapper around T[,]: public interface IGrid<T> where T : struct { Point Size { get; } T ...
0
votes
1answer
356 views

Is a PHP array an example of a dynamic data structure?

I did my homework, and it says that dynamic data structures are "data structures that change in size as a program needs it to by allocating and de-allocating memory from the heap". So I was ...
1
vote
1answer
93 views

If a variable containing a function gave the function's return instead of a reference to the function, what would an array of functions return? [closed]

I'm creating a prototype scripting language similar to something like Javascript. In my language, every single reference to a variable is actually a function call (a getter function), whether it has ...
1
vote
3answers
288 views

Choice between 1-dimensional and 2-dimensional array

I'm implementing the Chessboard class to represent the chessboard. I've to implement the transformations (reflections and rotations) on the chess board possible. The possible transformations includes ...
0
votes
3answers
148 views

Sorting an array when values are decreased by each swap [closed]

Recently in an interview I come across a question: We have an unsorted array, we need to sort it with minimum number of swap. We have in sort a 'tax' of 1 is deducted from the number we are ...
-1
votes
1answer
92 views

Fortran 90 - How to create a coordinate system

So I need to code a simple program, and I need to define 2D coordinates? Is there any coordinate system I can use in Fortran? I was told it might have to be all in arrays? And if so, can anybody ...
0
votes
2answers
267 views

Quick algorithm to find matches between two arrays

I'm faced with the following problem: I have an array which is produced by the parsing of a yaml file which contains patterns in the following structure. "Programming books" Title: a ...
2
votes
3answers
458 views

How do you read this line of code?

Forgive me for my poor English, me and my friend were doing school homework, suddenly he asked me to read this line of code ptr = &array[1][1][1] (ptr is a pointer to an integer). He said ...
4
votes
2answers
4k views

Should I use a list or an array?

I'm working on a windows form to calculate UPC for item numbers. I successfully create one that will handle one item number/UPC at a time, now I want to expand and do it for multiple item ...
0
votes
1answer
77 views

What is a cross-platform way to expose an Array[][] over a webservice? Any JSON nuances to be aware of?

I need to expose an Array[][] to many different clients (iPhone, Android, PC, Unix, etc), and need to make it available over HTTP/s This brings me to JSON, and makes me wonder how do all the other ...
0
votes
2answers
295 views

PHP SplFixedArray How To Deal With billions of indexes?

I've built a flatfile db system that will work like mini-noSQL system and it split db to smaller files, and I did a SplFixedArray wrapper for it with a method for searching usage built on preg_grep. ...
1
vote
3answers
519 views

Arrays vs Objects in view template

I am wondering, in view templates, what would contribute to me choosing between using arrays or objects for getting things printed out in arrays {{$user->zip_code}} vs {{$user['zip_code']}} I'm ...
1
vote
4answers
231 views

Is it considered bad practice to access a returned array by a key straight away?

I couldn't think of a good way to word the title, sorry. But what I mean is, is it considered bad practice to do: print get_array()[2] over: output=get_array() print output[2] (where get_array() ...
-1
votes
3answers
533 views

Find all lines segments intersections

I have a collection of lines segments, represented by an array. Ex: [3,7,13,6,9] is 4 line segments: [(3,7)(7,13)] , [(7,13)(13,6)] , [(13,6)(6,9)] , ([6,9)(9,3)] I want to find all the lines ...
-1
votes
5answers
1k views

Reverse subarray of an array with O(1)

I have an idea how to implement sub array reverse with O(1), not including precalculation such as reading the input. I will have many reverse operations, and I can't use the trivial solution of O(N). ...
3
votes
2answers
168 views

What would be the optimal way to solve a problem like this?

I have a problem where I have to change all the Xs in a 2D array into 0s, and I have to calculate the minimum steps (where a single step consists of changing an entire row or column) required to do ...
2
votes
3answers
240 views

What language has integrated “list insertion” as part of code *syntax*?

Many programming languages permit natural manipulation of strings, and some languages permit the manipulations of lists too. More often then not (always?), these operations are done as procedure ...
2
votes
6answers
362 views

Settle an Argument: String vs. Array?

True or False: A string is the same thing as an array. I had an interview the other day and the above question was asked. I said false, but the interviewer said it was actually true. I explained to ...
0
votes
1answer
373 views

Use ruby's array sort() method, or add items in correct place with a binary lookup?

If I am loading a whole load of items (un-ordered words from a file or something) would it be more efficient to load them all to a Ruby array, and then use the built in sort! method or to do a binary ...
0
votes
1answer
288 views

Sort rectangles in a grid based on a comparison of the center point of each

If I have a grid of rectangles and I move one of the rectangles, say above and to the left of another rectangle, how would I resort the rectangles? Note the rectangles are in an array, so each ...
3
votes
2answers
590 views

CA1819: Properties should not return arrays. Does this happen only with arrays? If yes, why?

I have a question about CA1819 msdn performance warning. The rule is: Arrays returned by properties are not write-protected, even if the property is read-only. To keep the array tamper-proof, the ...
2
votes
3answers
1k views

Specific reasons to create own array class over using std::array?

What specific conditions or requirements should you create your own array over using std::array? Here is my background: I'm developing a small simple library that a small group of people will use ...
2
votes
3answers
493 views

Best way to choose random element from weighted list

I want to create a simple game. Every so often, a power up should appear. Right now the different kinds of power ups are stored in an array. However, not every power up should appear equally often: ...
1
vote
4answers
166 views

Efficient way of evaluating an array of strings then add to an array in Ruby

I am looking for an efficient way of evaluating an array of strings against a series of rules and then adding them to another array. For example I have an array of strings: something a 1234 #gohere ...
-3
votes
2answers
2k views

Java: The best way to learn it when MOOCs and books are not enough? [closed]

This topic was taken from Stack Overflow, but it was put on-hold due to Opinion-based question. So I moved it to here. I've had some great troubles with my homework exercises and I've used ...
1
vote
1answer
291 views

ruby-idiomatic hashes vs arrays

So I am still fairly new to ruby, though I have noticed that it is very hard to create 2d-array and that hashes seem to be more of the go to data structure than arrays. I was wondering why the Ruby ...
1
vote
1answer
155 views

What is the name of this array transformation?

Start with an array of arrays; in this case, they are different lengths in order to demonstrate the technique, but they do not have to be. [[1,2,3,4], [5,6,7], [8,9,10], [11,12,13,14,15]] At the ...
4
votes
2answers
591 views

Array Multiplication and Division

I came across a question that (eventually) landed me wondering about array arithmetic. I'm thinking specifically in Ruby, but I think the concepts are language independent. So, addition and ...
2
votes
1answer
110 views

Handling Dynamic amount of Strings for persistent and runtime storage in an IOS App

Background I am dynamically building an FQL query statement and because of the nature of the app, I exclude FB family members, this is the base portion of the query and remains fairly static. The ...
0
votes
1answer
1k views

Sorting an ArrayList by a Split Value [closed]

I am attempting to create an list which should be sorted by a particular field in a colon separated string. I have an array of strings with the following values: name1:535 name2:697 After sorting ...
4
votes
2answers
501 views

Implementing non-fixed length array support in a compiler

I'm thinking of building a language for PIC microcontrollers. I want to be able to use non-fixed size arrays, like this: Declare the variable as int[] Wait for input from serial connection Make the ...
3
votes
4answers
1k views

Retrieving maximum value from a range in unsorted array

I have an unsorted array. I have queries in which I give a range and then the maximum value from that range has to returned. For example: array[]={23,17,9,45,78,2,4,6,90,1}; query(both inclusive): 2 ...
2
votes
4answers
1k views

How do you find the first common element in two arrays

The way I did it was to loop through each at the same time and add the current value to a separate set for each of the lists. Also, check if the current element is already in the other list's set. I ...
-4
votes
1answer
746 views

Program to verify all words in a crossword puzzle are valid

I have my own solution and wanted to check it against something online but couldn't find any examples. How would you solve this one. (I can post my code if necessary). I just want to see if someone ...
5
votes
2answers
308 views

Which design pattern is illustrated by inheriting IStructuralComparable interface?

We know that some design patterns are found so useful that they become features of the language itself. For instance, the interface IEnumerator which is implemented by Array object. This helps in ...
0
votes
3answers
461 views

A simple algorithm for finding duplicate floats [closed]

We have N numbers(real numbers(float)).They can be positive or negative or anything we do not know except the fact that there is exactly one number which has a duplicate and the rest all are distinct. ...
3
votes
1answer
643 views

The array class in C# - Implementation questions

I am studying the Array class in C#. The following is the implementation of System.Array class: [SerializableAttribute] [ComVisibleAttribute(true)] public abstract class Array : ICloneable, IList, ...