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/**
 * @param {number} k
 */
var MyCircularQueue = function(k) {
    this.k = k;
    this.arr = new Array(this.k);
    this.headIdx = -1;
    this.tailIdx = -1;
};

/** 
 * @param {number} value
 * @return {boolean}
 */
MyCircularQueue.prototype.enQueue = function(value) {
    if(this.isFull()){
        return false;
    }
    if(this.isEmpty()){
        this.headIdx = 0;
    }
    this.tailIdx = (this.tailIdx + 1) % this.k;
    this.arr[this.tailIdx] = value;
    return true;
};

/**
 * @return {boolean}
 */
MyCircularQueue.prototype.deQueue = function() {
    if(this.isEmpty()) {
        return false;
    }
    if(this.headIdx === this.tailIdx) {
        this.headIdx = -1;
        this.tailIdx = -1;
    } else {
        this.headIdx = (this.headIdx + 1) % this.k;
    }
    return true;
};


/**
 * @return {number}
 */
MyCircularQueue.prototype.Front = function() {
    if(this.isEmpty()) {
        return -1;
    }
    return this.arr[this.headIdx];
};

/**
 * @return {number}
 */
MyCircularQueue.prototype.Rear = function() {
    if(this.isEmpty()) {
        return -1;
    }
    return this.arr[this.tailIdx];
};

/**
 * @return {boolean}
 */
MyCircularQueue.prototype.isEmpty = function() {
    return this.headIdx === -1;
};

/**
 * @return {boolean}
 */
MyCircularQueue.prototype.isFull = function() {
    return ((this.tailIdx + 1) % this.k) === this.headIdx;
};

/**
 * Your MyCircularQueue object will be instantiated and called as such:
 * var obj = new MyCircularQueue(k)
 * var param_1 = obj.enQueue(value)
 * var param_2 = obj.deQueue()
 * var param_3 = obj.Front()
 * var param_4 = obj.Rear()
 * var param_5 = obj.isEmpty()
 * var param_6 = obj.isFull()
 */