数据结构与算法JavaScript描述——队列

<script type="text/javascript">
function Queue(){
    this.dataStore = [];
    this.enqueue = enqueue;
    this.dequeue = dequeue;
    this.front = front;
    this.back = back;
    this.toString = toString;
    this.empty = empty;
}

/**
*    向队尾添加一个元素
*/
function enqueue(element){
    this.dataStore.push(element);
}

/**
*    删除队首的元素：
*/
function dequeue(){
    this.dataStore.shift();
}

/**
*    读取队首的元素：
*/
function front(){
    return this.dataStore[0];
}

/**
*    读取队尾的元素：
*/
function back(){
    return this.dataStore[this.dataStore.length - 1];
}

/**
*    显示队列内的所有元素
*/
function toString(){
    var retStr = "";
    for (var i = 0; i < this.dataStore.length; ++i) {
        retStr += this.dataStore[i] + "\n";
    }
    return retStr;
}

/**
*    判断队列是否为空
*/
function empty(){
    if(this.dataStore.length == 0){
        return true;
    }else{
        return false;
    }
}

//测试代码
var q = new Queue();
q.enqueue("Meredith");    
q.enqueue("Cynthia");
q.enqueue("Jennifer");
console.log(q.toString());
q.dequeue();
console.log(q.toString());
console.log("Front of queue: " + q.front());
console.log("Back of queue: " + q.back());



</script>