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const EAST = "East";
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const NORTH = "North";
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const WEST = "West";
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const SOUTH = "South";
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const DIRECTIONS = [EAST, NORTH, WEST, SOUTH];
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const ORIGIN = [0, 0];
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/**
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 * @param {number} width
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 * @param {number} height
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 */
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var Robot = function (width, height) {
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  this.width = width;
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  this.height = height;
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  this.path = []; // circular buffer of entire path of robot
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  this.dirAtSquare = []; // dir robot is facing at each square
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  this.currentPos = -1;
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  this.preprocess();
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};
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/**
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 * Loop around the map once and store the path into a circular buffer.
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 *
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 * (0,0) is set to face SOUTH. The only time it is EAST is at the beginning
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 * if the robot didn't move at all.
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 *
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 * @return {void}
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 */
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Robot.prototype.preprocess = function () {
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  // go right
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  for (let i = 1; i < this.width; i++) {
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    this.path.push([i, 0]);
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    this.dirAtSquare.push(0);
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  }
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  // go up
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  const xMax = this.width - 1;
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  for (let i = 1; i < this.height; i++) {
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    this.path.push([xMax, i]);
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    this.dirAtSquare.push(1);
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  }
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  // go left
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  const yMax = this.height - 1;
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  for (let i = xMax - 1; i >= 0; i--) {
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    this.path.push([i, yMax]);
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    this.dirAtSquare.push(2);
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  }
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  // go down
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  const xMin = 0;
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  for (let i = yMax - 1; i >= 0; i--) {
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    this.path.push([xMin, i]);
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    this.dirAtSquare.push(3);
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  }
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};
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/**
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 * @param {number} num
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 * @return {void}
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 */
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Robot.prototype.step = function (num) {
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  this.currentPos += num;
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};
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/**
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 * @return {number[]}
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 */
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Robot.prototype.getPos = function () {
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  return this.currentPos === -1
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    ? ORIGIN // we haven't moved
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    : this.path[this.currentPos % this.path.length];
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};
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/**
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 * @return {string}
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 */
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Robot.prototype.getDir = function () {
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  return this.currentPos === -1
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    ? DIRECTIONS[0] // we haven't moved
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    : DIRECTIONS[this.dirAtSquare[this.currentPos % this.dirAtSquare.length]];
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};
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/**
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 * Your Robot object will be instantiated and called as such:
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 * var obj = new Robot(width, height)
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 * obj.step(num)
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 * var param_2 = obj.getPos()
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 * var param_3 = obj.getDir()
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 */