RLE 迭代器

RLE_Iterator.js

/**
 * @param {number[]} A
 */
var RLEIterator = function(A) {
    this.data =A;
    this.count = this.data.shift()||0;
    this.num   = this.data.shift(); 
};

/** 
 * @param {number} n
 * @return {number}
 */
RLEIterator.prototype.next = function(n) {
    this.count -= n;
    while(this.count<0 && this.data.length>0){
        this.count += this.data.shift();
        this.num    = this.data.shift();
    }
    if(this.count <0) {
        return -1;
    }else {
        return this.num;
    }
};

/** 
 * Your RLEIterator object will be instantiated and called as such:
 * var obj = new RLEIterator(A)
 * var param_1 = obj.next(n)
 */