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2069. Walking Robot Simulation II 👎

  • Time:
    • Constructor: $O(\texttt{width} + \texttt{height})$
    • step(num: int): $O(1)$
    • getPos(): $O(1)$
    • getDir(): $O(1)$
  • Space: $O(\texttt{width} + \texttt{height})$
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class Robot {
 public:
  Robot(int width, int height) {
    pos.push_back({{0, 0}, "South"});
    for (int i = 1; i < width; ++i)
      pos.push_back({{i, 0}, "East"});
    for (int j = 1; j < height; ++j)
      pos.push_back({{width - 1, j}, "North"});
    for (int i = width - 2; i >= 0; --i)
      pos.push_back({{i, height - 1}, "West"});
    for (int j = height - 2; j > 0; --j)
      pos.push_back({{0, j}, "South"});
  }

  void step(int num) {
    isOrigin = false;
    i = (i + num) % pos.size();
  }

  vector<int> getPos() {
    return pos[i].first;
  }

  string getDir() {
    return isOrigin ? "East" : pos[i].second;
  }

 private:
  bool isOrigin = true;
  int i = 0;
  vector<pair<vector<int>, string>> pos;
};

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class Robot {
  public Robot(int width, int height) {
    pos.add(new Pair<>(new int[] {0, 0}, "South"));
    for (int i = 1; i < width; ++i)
      pos.add(new Pair<>(new int[] {i, 0}, "East"));
    for (int j = 1; j < height; ++j)
      pos.add(new Pair<>(new int[] {width - 1, j}, "North"));
    for (int i = width - 2; i >= 0; --i)
      pos.add(new Pair<>(new int[] {i, height - 1}, "West"));
    for (int j = height - 2; j > 0; --j)
      pos.add(new Pair<>(new int[] {0, j}, "South"));
  }

  public void step(int num) {
    isOrigin = false;
    i = (i + num) % pos.size();
  }

  public int[] getPos() {
    return pos.get(i).getKey();
  }

  public String getDir() {
    return isOrigin ? "East" : pos.get(i).getValue();
  }

  private boolean isOrigin = true;
  private int i = 0;
  private List<Pair<int[], String>> pos = new ArrayList<>();
}

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class Robot:
  def __init__(self, width: int, height: int):
    self.isOrigin = True
    self.i = 0
    self.pos = ([((0, 0), 'South')] +
                [((i, 0), 'East') for i in range(1, width)] +
                [((width - 1, j), 'North') for j in range(1, height)] +
                [((i, height - 1), 'West') for i in range(width - 2, -1, -1)] +
                [((0, j), 'South') for j in range(height - 2, 0, -1)])

  def step(self, num: int) -> None:
    self.isOrigin = False
    self.i = (self.i + num) % len(self.pos)

  def getPos(self) -> list[int]:
    return self.pos[self.i][0]

  def getDir(self) -> str:
    return 'East' if self.isOrigin else self.pos[self.i][1]