Vector of C ++ sequential containers, vector of sequential containers
What is container
Container, as its name implies, is a place for storing things. C ++ containers store certain data structures for data search or sorting or other special purposes. As we all know, common data structures are similar to arrays.Array, Linked listList, TreeTreeStackStack, QueueQueue, HashHash Table, SetSet, I
Vector
Vectors are collections of objects of the same type. Each object in the collection has a corresponding index. Vectors are often referred to as containers (container).To use vectors, you need to:
#include
The vector is a class template (classes template). C + + has functional templates and class templates. The template itself is not a function or class, it must be instantiated by the co
Excerpt from: http://blog.csdn.net/fxjtoday/article/details/5142661Leveraging term vectorsThe so-called term vector, which is a field of documents, such as the text type of title,body, establishes the multidimensional vector space of word frequency . Each term is one dimension, and the value of this dimension is the frequency of the word in this field.If you want to use term vectors, you will need to open t
Transfer from the blog garden: https://www.cnblogs.com/zhonghuasong/p/5975979.htmlIntroduced
A vector is a sequence container that represents a variable-sized array.
Like arrays, vectors also use contiguous storage spaces to store elements. That means you can use the subscript to access the elements of the vector, as well as the arrays. But unlike an array, its size can be changed dynamically,
Before doing a bit of something, to fit 6 and plus, do your own cut map to find it really annoying enough. The method of generating PNG graphics based on vector graph is also afterwards know, study, hope next can practice. Enter the translation below.
The visual form of iOS applications is usually driven by graphical elements. When designing and developing an application, you need different specifications for application icons, such as default.png pi
Previously only used vectorFirst, JTable and DefaultTableModel.JTable itself is a list that can be displayed, but cannot be monitored by the button to increase the positive row data.JTable no AddRow (object[] rowdata) or addrow (Vector rowdata), method.But there is a construction method in JTable, JTable (TableModel DM)And TableModel is an interface that implements this interface with a common class DefaultTableModel. There is a method in DefaultTable
Data Growth:When you need to increase, VectorThe default growth is the original one training, andArraylistHalf of the originalSynchronization: the vector is thread-safe, that is, synchronous, And the arraylist is a line.ProgramNot secure, not synchronous
Here we can look at their source code to know:
The size () method of arraylist:
1 /**2 * Returns the number of elements in this list.3 *4 *@ ReturnThe number of elements in this list5*/6Public In
Vector or arraylist-which one is better? Why?
The answer to this question cannot be generalized. Sometimes it is better to use vector. Sometimes it is an arraylist. Sometimes neither of them is
The best choice. Don't expect a simple affirmative answer, because it depends on what you use them. Four of the following are to be considered:
Factors:
L API
L synchronous processing
L data growth
L usage mode
We wi
Label: style blog HTTP color OS Io ar Div html When setting the CPU parameters during the learning process of the nioshi II, the Reset vector and exception vector settings are encountered. Shows the parameter setting screen. Reset vector -- Reset vectorException vector -- execution VectorFirst, it indicates that both
mentioned. This is the function interval.
Description :A: Taking two-dimensional space as an example, the linear equation is changed to +c=0 ax+by+c=0.
The usage vector w instead (A, b) is represented by the feature vector x, which is the formula.B: For the straight line we learned. By substituting the negative instance point (0,0), we can see that the calculated result +1 is inconsistent with
STD: Difference Between Reserve and resize of Vector1. Reserve: Allocate space, change capacity but not size2.Resize: Allocate space. Changing the capacity also changes the size.
If you know the vector size, resize it as an array without allocating extra memory.
ReserveIt is a container reserved space, but does not actually create element objects. Before creating an object, you cannot reference the elements in the container. Therefore, when add
There is a copy function in the STL algorithm. We can easily write this code:#include #include #include using namespace STD;int_tmain (intARGC, _tchar* argv[]) {Doubledarray[Ten]={1.0,1.1,1.2,1.3,1.4,1.5,1.6,1.7,1.8,1.9}; vectordouble>Vdouble (Ten); vectordouble>:: Iterator Outputiterator=vdouble.begin (); Copy (darray,darray+Ten, Outputiterator); while(Outputiterator!=vdouble.end ()) {coutreturn 0;}So you want to use copy to set the to vector, so you
Dynamically assigned vector pointer Vector If it is a dynamically allocated vector pointer, you can only use the array method (the above Code is red) when inserting elements into the vector. the push_back () function has an error. Why? Use the shared_ptr vector point
Previous blogs have written about vectors using the sort algorithm, and vector some of the processing methods that have been written before.Just write it today vector . Sort by using the sort algorithm.#include #include #include #include #include BOOLCompare_int (intAMP;LHS,int RHS) {returnLHS > RHS;}BOOLCompare_first_letter (Const STD::unique_ptrSTD::string> AMP;LHS,Const STD::unique_ptrSTD::string> RHS)
The arraylist, inclulist, and vestor classes all implement the java. util. List interface, but they have different features, mainly as follows:
I,Synchronization
Arraylist and inclulist are not synchronized, while vestor is. Therefore, if thread security is required, arraylist or javaslist can be used to save costs for synchronization. But in the case of multithreading, sometimes we have to use vector. Of course, you can also package arraylist and his
Vector series in practice c ++ -- sort the vector (unique_ptr (string) using the sort algorithm (sort function error "two parameters should be input, but three parameters are provided)
Previously, I wrote a blog post on sorting the vector using the sort algorithm.vector
>
.
Today, let's write a pairvector
>
Use the sort algorithm for sorting.
# In
In practice, the vector series in c ++ -- vector (unique_ptr () initialization (Ownership Transfer)
C ++ 11 provides us with smart pointers and brings us a lot of convenience.
What if unique_ptr is used as an element of the vector container?
The format is exactly the same:vector
> vec;
But how to add elements to vec?
See the following:
# Include
Vector initialization and traversal-dtor-blog
Vector initialization and traversal
STD: Vector
Int
>
Inttest; For(IntI=0; I10;++I){Inttest. push_back (I );} For (STD: Vector Int > : Iterator ITER = Inttest. Begin (); ITER ! = Inttest. End (); ++ ITER){STD: cout * ITER STD: Endl
For vector usage, the additional time consumed by copying data to prevent reallocate memory.
The following two combinations can be used to prevent reallocate.
1. Vector: resize () using array index
2. Vector: Reserve () Use push_back ().
So I tested these two cases on the Windows 2003 platform, and compared them with 3 in which push_back () is directly
Today we want to use vector to realize the function of two-dimensional array, and try to put the two-dimensional vector. Who knows when he got started, he met Ray.
The form of the code is roughly as follows:
VECTOR
The vacuuming operation was performed because the two-dimensional vector was reused. However, th
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