数据结构与算法javascript描述（二）优先队列实例

左手的ㄟ右手 2022-08-10 00:50 271阅读 0赞

/* 
    优先队列：从优先队列中删除元素时， 需要考虑优先权的限制。
    数组实现队列
    */
    function Queue(){
        
         this.dataStore = [];
         this.enqueue = enqueue;
         this.dequeue = dequeue;
         this.front = front;
         this.back = back;
         this.toString = toString;
         this.empty = empty;
        }
        function enqueue(element){
        
            this.dataStore.push(element);
        }
    //优先码的值最小的元素优先级最高。  dequeue() 方法遍历队列的底层存储数组， 从中找出优先码最低的元素， 然后使用数组的 splice() 方法删除优先级最高的元素。
        function dequeue(){
        
            var priority = this.dataStore[0].code;
            for(var i = 1; i<this.dataStore.length; ++i){
              if (this.dataStore[i].code < priority){
                  priority = i;
              }
            }
           return this.dataStore.splice(priority,1);
        }
    
    
        function front(){
        
    
           return this.dataStore[0];
    
        }
        function back(){
        
            return this.dataStore[this.dataStore.length-1];
        }
        function toString(){
        
            var retStr = "";
            for (var i=0;i<this.dataStore.length;++i){
                retStr += this.dataStore[i]+"\n";
            }
            return retStr;
    
        }
        function empty(){
        
            if(this.dataStore.length == 0){
                return true;
            }
            else{
                return false;
    
            }
        }
    
    function Patient(name,code){
        
        this.name = name;
        this.code = code;
    }
    
    
    
    function toString(){
        
       var retStr = "";
       for(var i = 0;i<this.dataStore.length;++i ){
        retStr +=this.dataStore[i].name + "code: "+this.dataStore[i].code+"n";
       }
     return retStr;
    }

测试

//优先队列的实现
    
    var p = new Patient("dwx",5);
    var ed = new Queue();
    ed.enqueue(p);
    p = new Patient("wbw",4);
    ed.enqueue(p);
    p = new Patient("czb",6);
    ed.enqueue(p);
    p = new Patient("wl", 1);
    ed.enqueue(p);
    p = new Patient("hdw",1);
    ed.enqueue(p);
    console.log(ed.toString());
    var seen = ed.dequeue();
    console.log("Patient being treated: " + seen[0].name );
    console.log("Patient waiting to be seen: ")
    console.log(ed.toString());
    var seen = ed.dequeue();
    console.log("Patient being treated: " +seen[0].name);
    console.log("Patients waiting to be seen :")
    console.log(ed.toString());