In C++ STL, Queue is a type of container that follows FIFO (First-in-First-Out) elements arrangement i.e. the elements which insert first will be removed first. In queue, elements are inserted at one end known as "back" and are deleted from another end known as "front".

在C ++ STL中，队列是遵循FIFO(先进先出)元素排列的一种容器，即，首先插入的元素将被首先删除。 在队列中，元素被插入称为“ back”的一端，并从称为“ front”的另一端删除。

Note: In the , "push" is an operation to insert an element in any container, "pop" is an operation to remove an element from the container.

注意：在 ， “ push”是在任何容器中插入元素的操作， “ pop”是从容器中删除元素的操作。

1)C ++ STL队列:: push()函数 (1) C++ STL queue::push()function)

push() inserts an element to queue at the back. After executing this function, element inserted in the queue and its size increased by 1.

push()在后面插入一个要排队的元素。 执行此功能后，插入队列中的元素及其大小增加了1。

Syntax:

句法：

queue_name.push(element);

2)C ++ STL queue :: pop()函数 (2) C++ STL queue::pop() function)

pop() removes an element from the front of the queue. After executing this function, the oldest element removed from the queue and its size decreased by 1.

pop()从队列的开头删除一个元素。 执行此功能后，最旧的元素从队列中删除，其大小减小了1。

Syntax:

句法：

queue_name.pop();

Program:

程序：

// cpp program for queue implementation // Example of push() and pop()#include 
    
     #include 
     
      using namespace std;//function to print the queue void printQueue(queue
      
        q){
   	// printing content of queue	while (!q.empty()) {
   		cout<<" "<