the container to be reserved. The resize function can have two parameters, the first parameter is the new container size, and the second parameter is to add new elements in the container. If this parameter is omitted, the default constructor of the element object is called. The following are examples of the two functions:
???? Vector
Because the source code of the two interfaces is quite simplified, You can paste them here:
?? Void? Resize (size_
C++11 provides us with smart pointers, which brings us a lot of convenience.So what if the unique_ptr is the element of a vector container?form the same:vectorBut how do you add elements to VEC?See below:#include#include#include usingnamespacestd;int main(){ vectorint>> vec; vec.push_back(1);//错误 return0;}First define a unique_ptr and then Push_back ():#include#include#include usingnamespacestd;int main(){ vectorint>> vec; unique_ptrint
C++11 provides us with smart pointers, which brings us a lot of convenience.What about the assumption that unique_ptr is the element of a vector container?form the same:vectorBut how do you add elements to VEC?See below:#include#include#include usingnamespacestd;int main(){ vectorint>> vec; vec.push_back(1);//错误 return0;}First define a unique_ptr and then Push_back ():#include#include#include usingnamespacestd;int main(){ vectorint>> vec;
1. DefinitionVector2. Inserting elementsIf you want to define a = [[0,1,2],[3,4,5]], then:Correct insertion method vectorWrong insertion method vector3. LengthThe number of vector elements in vector About the use of vector
Test source#include2. Compiling3. Remove the random base address (for easy search)Instead of 04. Use Ida to open the call function in the main function5. Select address with OD load view6.call very much only look at the key to find the constructor of the vector with the object base address find something with Ida debugging with OD7. Run to the next break data followSure is CC.8. Run constructorsInitialization (STL objects have a feature the first one
Use vector containers, that is, to avoid the search, so today we list some STL find algorithm applied to the vector.
Find ()Returns an iterator to the "the" in the range [First,last] that compares equal to Val. If no such element is found, the function returns last.
#include
find_end () searches the range [first1,last1) for the "Last occurrence of" sequence defined by [ FIRST2,LAST2), and returns a i
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)
Requirements
Required knowledge
This article requires a basic understanding of html and css front-end code.
Running EnvironmentStandard browser, compatible with IE7
Source code download
Font Awesome provides you with a set of scalable Font vector icons that can quickly customize the size, color, and shadow of the icons. These can be achieved through CSS, no JS code is required.
3. Use CSS to customize the Icon size, color, and shadow.
5. Supp
The data structure we implement is to solve the dynamic open-up space usage during the running process (for example, we do not know how much we enter without stopping the input)
Two principles:
I. Stupid Methods
How much space is used and how much space is opened for the first time?
The second time we use space, we will open up space B larger than the first one, copy the data in A to B, then release a, and write new data in C.
Disadvantage: copying is too many times and the efficiency is lo
Establishing equationsSet a to a point outside the line,B,c to two points in a straight line$\left\{\begin{matrix}(X-ax,y-ay) \cdot (cx-bx,cy-by) =0 \\FRAC{Y-CY}{X-CX}=\FRAC{Y-BY}{X-BX} \\end{matrix} \right.$?Solve the symbolic solutionUsing the Mathematics tool:
solve[{(x?-? Ax) * (CX?-? bx)? +? ( Y?-? ay) * (Cy?-? by)? = =???
??? 0,? (y?-? Cy) * (x?-? bx)? = =? (y?-? by) * (x?-? cx)},? {x,?y}]??
Come to the following:
{{x?->?-(bx?-? cx)? ( Ax?bx?+?ay?by?-? ax?cx?-? a
For example, I have a piece of code as follows:
Class cls_vector_item
There is no problem with this code.
When VCT. push_back (CVI);, when the internal space of VCT is insufficient, a new space will be applied and the object will be removed!
However, note that this object should have been removed, but the internal object of the object we are currently in will be removed, but it will become garbage, that is, when the VCT applies for space, the old space is destructed, but our objects are st
for the following part of the code, the VS2010 Windows platform prompts the array to cross (compile through, execute EXE prompts) but the codeblock is normal under deep Linux.
The first form of
/*vector
... 1.OutLineHand is a custom encapsulated contour class that contains data members and member functions. 2.filterContours is the vector 3.OutLineHand is a custom encapsulated contour clas
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
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