queue

queue用法

push(T e) 入队操作

pop() 出队操作

empty() 判空，为空返回ture

size() 返回队列的大小

front() 队头元素

back() 队尾元素

不能使用迭代器遍历每个元素

测试

#include <iostream> #include <queue> using namespace std; void printQueue(queue<int>& q){ cout << endl << "--------- Queue Info --------" << endl; cout << "[ " << q.back() << " --> " << q.front() << " ] "; cout << " ( size : " << q.size() << " )" << endl; } int test(){ queue<int> myQueue; cout << "初始化空队列, empty(): " << myQueue.empty() << endl; int n; cout << endl << "输入队列元素，也空格分开，Ctrl + Z 结束 ：" << endl; while (cin >> n)myQueue.push(n); printQueue(myQueue); cout << endl << "Now, Let's pop() " << endl; myQueue.pop(); cout << endl << "Let's push(15) " << endl; myQueue.push(15); printQueue(myQueue); return 0; }

结果

初始化空队列, empty(): 1 输入队列元素，也空格分开，Ctrl + Z 结束 ： 21 123 421 123 21 13^Z --------- Queue Info -------- [ 13 --> 21 ] ( size : 6 ) Now, Let's pop() Let's push(15) --------- Queue Info -------- [ 15 --> 123 ] ( size : 6 ) 请按任意键继续. . .

deque用法

deque是双向队列Double ended queue；can be accessed with random access iterator

deque是双端队列，是可以在两端扩展和收缩的连续容器。一般deque的实现是基于某种形式的动态数组，允许单个元素用随机获取

迭代器随机读取，数组容量自动管理。

因此它有和vector相似的函数，但在序列的开始也有高效的插入和删除。但不像vector，deque的元素并不是严格连续存储的。

vector和deque有相似的接口和相似的目的，但内部实现截然不同。

push_front(T e) 从队头入队操作

pop_front() 从队头出队操作

push_back(T e) 从队尾入队操作

pop_back() 从队尾出队操作

empty() 判空，为空返回ture

size() 返回队列的大小

front() 队头元素

back() 队尾元素

可以使用迭代器访问每个元素

for (myItor = d.begin(); myItor != d.end(); myItor++) cout << *myItor << " ";

测试

#include <iostream> #include <deque> using namespace std; void showDeque(deque<int>& d){ deque<int>::iterator myItor; cout << "[ "; for (myItor = d.begin(); myItor != d.end(); myItor++) cout << *myItor << " "; cout << "]" << endl; } void push_front(deque<int>& d, int e){ d.push_front(e); cout << "Now, push_front e = " << e <<", deque is :"<< endl; showDeque(d); } void push_back(deque<int>& d, int e){ d.push_back(e); cout << "Now, push_back e = " << e << ", deque is :" << endl; showDeque(d); } void pop_front(deque<int>& d){ d.pop_front(); cout << "Now, pop_front, deque is :" << endl; showDeque(d); } void pop_back(deque<int>& d){ d.pop_back(); cout << "Now, pop_back, deque is :" << endl; showDeque(d); } int test() { deque<int> myDeque; push_front(myDeque, 1); push_front(myDeque, 2); push_back(myDeque,3); push_back(myDeque, 4); push_back(myDeque, 5); push_front(myDeque, 6); pop_back(myDeque); pop_front(myDeque); return 0; }

结果

Now, push_front e = 1, deque is : [ 1 ] Now, push_front e = 2, deque is : [ 2 1 ] Now, push_back e = 3, deque is : [ 2 1 3 ] Now, push_back e = 4, deque is : [ 2 1 3 4 ] Now, push_back e = 5, deque is : [ 2 1 3 4 5 ] Now, push_front e = 6, deque is : [ 6 2 1 3 4 5 ] Now, pop_back, deque is : [ 6 2 1 3 4 ] Now, pop_front, deque is : [ 2 1 3 4 ] 请按任意键继续. . .

参考

c++ queue&dqueue