queue队列分析和总结.docxVIP

再学 再学 C++编程----queue 队列 数据结构 2009-11-17 11:39:22 阅读5 评论0字号：大中小 主题： 主题： 再学C++编程 queue 队列 Queue constructor //队列构造函数 Syntax: #include queue queue(); queue( const Container con ); //队列复制构造函数。 Queues have an empty constructor and a constructor that can be used to specify(指定的) a container type(容器对象). push() //进入队列 Syntax: #include queue void push( const TYPE val ); The function push() adds val to the end of the current queue. For example, the following code uses the push() function to add ten integers(整型值) to the end of a queue(队列): queueint q; for( int i=0; i 10; i++ ) q.push(i); pop() //出队列 Syntax: #include queue void pop(); The function pop() removes(删除) the top element of the queue and discards(扔掉，丢弃) it. size() //队列元素的个数。 Syntax: #include queue size_type size() const; The size() function returns the number of elements in the current queue. front() //队列首部的第一个元素。Syntax: #include queue TYPE front(); const TYPE front() const; The front() function returns a reference( 引 用 ) to the first element of the queue, and runs in constant(确定的，常量) time. back() //队列尾部的最后一个元素。Syntax: #include queue TYPE back(); const TYPE back() const; The back() function returns a reference to the last element in the queue. For example: vectorint v; for( int i = 0; i 5; i++ ) { v.push_back(i); } cout The first element is v.front() and the last element is v.back() endl; This code produces the following output: The first element is 0 and the last element is 4 The back() function runs in constant time. empty()// empty() //判断队列是否为空 Syntax: #include queue bool empty() const; The empty() function returns true if the queue has no elements, false otherwise. For example, the following code uses empty() as the stopping condition on a (C/C++ Keywords) while loop to clear(清空) a queue and display(显示) its contents in reverse(逆序) order: vectorint v; for( int i = 0; i 5; i++ ) { v.push_back(i); } while( !v.empty() ) { cout v.back() endl; v.pop_back(); }