Flatten 2D Vector

Description

null

Solution(javascript)

/**
 * 可以转成一维数组，然后迭代或者按需
 * @param {number[][]} v
 */
const Vector2D = function (v) {
  this.row = 0
  this.column = 0
  this.matrix = v
}

/**
 * @return {number}
 */
Vector2D.prototype.next = function () {
  if (this.row < this.matrix.length && this.column < this.matrix[this.row].length) {
    const value = this.matrix[this.row][this.column]
    this.column += 1
    return value
  }
  this.row++
  this.column = 0
  return this.next()
}

/**
 * @return {boolean}
 */
Vector2D.prototype.hasNext = function () {
  if (this.row >= this.matrix.length) {
    return false
  }
  if (this.column < this.matrix[this.row].length) {
    return true
  }
  this.row++
  this.column = 0
  return this.hasNext()
}