题目链接

    2. var MaxQueue = function() {
    3.   this.queue = [];
    4.   this.deque = [];
    5. };
    7. /**
    8.  * @return {number}
    9.  */
    10. MaxQueue.prototype.max_value = function() {
    11.   if(this.deque.length>0){
    12.     return this.deque[0];
    13.   }
    14.   return -1;
    15. };
    17. /** 
    18.  * @param {number} value
    19.  * @return {void}
    20.  */
    21. MaxQueue.prototype.push_back = function(value) {
    22.   while(this.deque.length>0 && value > this.deque[this.deque.length-1]){
    23.     this.deque.pop();
    24.   }
    25.   this.deque.push(value);
    26.   this.queue.push(value);
    27. };
    29. /**
    30.  * @return {number}
    31.  */
    32. MaxQueue.prototype.pop_front = function() {
    33.   if(this.queue.length === 0){
    34.     return -1;
    35.   }
    36.   let res = this.queue.shift();
    37.   if(res === this.deque[0]){
    38.     this.deque.shift();
    39.   }
    40.   return res;
    41. };