Home » What variations of vector-like containers already widely established? Do I have to write my own? [closed]

What variations of vector-like containers already widely established? Do I have to write my own? [closed]

Solutons:


Here are the ones I know of:

  • Traditional a.k.a. plain a.k.a. C array
  • vector
  • unique_ptr with an array-type template argument
  • array
  • valarray
  • dynarray
  • static_vector (see also here)
  • small_vector
  • stable_vector

There are also “variable-length arrays” and “arrays with runtime bounds”, which do not exist in C++; the former exists in C. See also this question and this answer about these non-C++ containers.

Let’s compare the features of all of these. If the container you want doesn’t match one of the lines below exactly, you’ll need to implement your own and choose a name for it.

Criterion C array array vector unique_ptr valarray dynarray static_vector small_vector stable_vector
Origin/library language std std std std discarded std Boost Boost Boost
Type parameters T,N T,N T,A T T T T,C,O T,N,A,O T,A
Capacity fix time Compile Compile Never (Construct) Never Construct Compile Never Never
Size fix time Compile Compile Never N/A Never Never Construct Never Never
Size = capacity always? N/A
Storage typically on Stack Stack Heap Heap Heap Heap Stack Stack/Heap Heap
Stable iterators? N/A N/A N/A N/A N/A (✔)
Constraint on element type

Template parameter legend:

  • A for allocator
  • T for element type
  • N for size in number of elements
  • C for capacity in number of elements
  • O for options

Finally, an interesting but less popular vector-like container is the “veque”, or deque-vector amalgam.

Related Solutions

How to remove repetition in output results in this code

You could put all your lines in a java.util.LinkedHashSet<String>. A Set means it will only keep distinct items. The reason we'll use a LinkedHashSet instead of a regular HashSet is to retain the input-order. After adding them all to the set, we print...

Can You decrypt this javascript?

the script is not encrypted, but obfuscated, But, to reduce your curiosity, see the script below after I've deobfuscated: var z = ["$(i)['f'](5(){$('#3')['j']('<a 4="2://6.7.8" c="d" e="b" g="h:9!0;k:1!0;l:m!0">تصميم:عبدو...

i do not understand this bfs algorithm code

The main thing you don't understand is std::pair http://www.cplusplus.com/reference/utility/pair/ which combines two types (or two of the same type) into the type of one object made from those two. Also notice the using namespace std; that lets the programmer...

How to save Answers in SQL?

The best way of saving multiple records into an sql server table from .Net is using a table valued parameter. First, you need to create a user defined table type (UDT) in your sql server: CREATE TYPE UDT_UserAnswers AS TABLE ( UserAnswers_UserId int,...

unlimited zero as output while running c++ in cpp driod

First off, you need to declare the variable j somewhere. Assuming you have declared j somewhere else in the program, this program as you have written it here will actually print nothing out. Since j is set to start at 0, and 0 is not greater than 0, the...

Android get text from editText

First initialize the editText just like you initialize the Button and TextView then you are able to get the text from editText you must have initialize. (EditText, input1 and input2). in Activity : EditText editTextView1; EditText editTextView2; String input1;...

T-SQL to generate expect result

Assuming that I understand the problem: you have a number of rows with sections ("Cates") and symbols ("Type"); if there are any symbols ending in a minus sign then these indicate a row without a minus sign should be removed; symbols are never "mixed" per...

retrieve contents of div and make image src

The button demonstrates that ablility. Use the button's onclick code wherever you need. <div id="flag-name" style="hidden">en-flag.jpg</div> <img id="myImage" /> <button...

Not getting correct javascript [closed]

So the mistake you're making is that if you loop through several things and hardcode the id, several elements get the same id, which is why your increase() function is updating the "wrong" elements. So you need to give each item in the loop a unique id. One way...

Leaderboard/Highscore for game in PHP

Rather than doing this psuedo: Scenario 1: // user exists // determine current score // update user, current score + new game score Scenario 2: // user does not exist // insert user with new game score Here, you're trying to keep a single row updated with the...

Copy content of one array to another arry

You can use Array.prototype.concat() var A = [1, 2, 3, 4]; var res = A.concat(A); console.log(A, res); I'd suggest to go with guest271314 answer. But if you want to multiply it more than twice, and you're looking for an alternative solution, you can also do it...

How to Make text appear and disappear on image after tapping.

Based on the code you provided, here is a solution that allows the visibility of a div to be toggled when the container is clicked using JavaScript: <style> /* Container holding the image and the text */ .container { position: relative; } /* Bottom right...

Explain the output obtained by using the following Macro

If you had considered the warnings you could have identified yourself macro1.c: In function ‘main’: macro1.c:11:3: warning: passing argument 1 of ‘printf’ makes pointer from integer without a cast [enabled by default] ABC(("Sum of x + y is %d", x + y)); ^ In...

Font scaling based on width of container

But what if the container is not the viewport (body)? This question is asked in a comment by Alex under the accepted answer. That fact does not mean vw cannot be used to some extent to size for that container. Now to see any variation at all one has to be...

How to send Some Value in Button to Textbox in c sharp? [closed]

Hi just add simple code to your buttons, Concern about validations and things. private void plusButton_Click(object sender, EventArgs e) { if (string.IsNullOrEmpty(textBox2.Text)) { int count = 0; textBox2.Text = count.ToString(); } else { int count =...

Clarification regarding content in my android app [closed]

Should i be worried about getting sued (if seen from other angle the source website will also make revenue from my app as their websites are being viewed) (i even show disclaimer saying "all articles belong to respective owners") Directly copying content even...

How do I prevent from writing a number that is already written?

Using a hashset, For every new number, check. If it already exist inside the hashset, ignore it else add it to the hash set and print it int[] numbers = new int[100]; HashSet<int> uniqueNums = new HashSet<int>(); for (int i=0; i < numbers.Length;...

Android code not working

Change your onCreate View like This: TextView textView; ImageView imageView; Button eat; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); textView = (TextView)...

Increase Boost regex speed or use PCRE in C++ [duplicate]

i used the boost and got better result (2 Min) You'd have to show me that to believe it !! Using benchmark software from this app RegexFormat that uses Boost, I get less than 3 seconds. The thing with that benchmark software is you can use a single test line...