deque method in C++

* create
```
#include <deque>
using namespace std;

int main() {
    deque<int> a;  // default constructor
    deque<int> b(a);  // copy constructor
    deque<int> c(move(a));  // move constructor
    deque<int> d{1,2,3};  // initializer list constructor
    deque<int> e(3,1);  // fill constructor
    deque<int> f(a.begin(),a.end());  // range constructor

    deque<int>* g = new deque<int>{1,2,3};  // new operator
    delete g;
}
```
* iterator
```
#include <iostream>
#include <deque>
using namespace std;

int main() {
    deque<int>c{1,2,3,4,5,1};

    for (auto i = c.begin(); i != c.end(); ++i)
        cout << *i << " ";
    cout<<endl;    
    for (auto i = c.cbegin(); i != c.cend(); ++i)
        cout << *i << " ";
    cout<<endl;    
    for (auto i = c.rbegin(); i != c.rend(); ++i)
        cout << *i << " ";
    cout<<endl;    
    for (auto i = c.crbegin(); i != c.crend(); ++i)
        cout << *i << " ";
    cout<<endl;    
}
/*
1 2 3 4 5 1 
1 2 3 4 5 1 
1 5 4 3 2 1 
1 5 4 3 2 1 
*/
```
* add
```
#include <iostream>
#include <deque>
using namespace std;

int main ()
{
    deque<int> dq;

    dq.push_back(1);
    dq.push_front(2);

    auto it = dq.end();
    dq.insert(it, 3);

    for (auto &i:dq)
        cout<<i<<",";
    cout<<endl;
}
```
* change
```
#include <iostream>
#include <deque>
using namespace std;

int main ()
{
    deque<int> a{1,2,3,4,5};
    deque<int> a1{1,2,3,4,5};

    *a.begin()=2;
    
    a[0]=1;
    a.at(1)=2;
    a.front()=3;
    a.back()=4;
    
    a1.assign(3, 5);
    a.swap(a1);
    
    for (auto &i:a)
        cout<<i<<";";
    cout<<endl;
}
```
* query
```
#include <iostream>
#include <deque>
using namespace std;

int main() {
    deque<int> a{};
    a.assign(10, 1);

    cout<<a.front()<<","<<a.back()<<endl;
    cout<<a.max_size()<<","<<a.empty()<<endl;    
}
```
* delete
```
#include <iostream>
#include <deque>
using namespace std;

int main() {
    deque<int> a{};
    a.assign(10, 1);

    a.pop_front();
    a.pop_back();
    a.erase(a.begin());
    a.clear();
    cout<<a.empty()<<endl;    
}
```
Home