yitonghe00

class PGroup {
  // Your code here
  constructor(values) {
    this.values = values;
  }
  
  add(elem) {
    if (this.has(elem)) {
      return this;
    } else {

yitonghe00

// Your code here
function yourRobot({place, parcels}, route) {
  if (route.length == 0) {
    const routes = parcels.map(parcel => {
      let route, pickingUp = false;
      if (parcel.place != place) {
        route = findRoute(roadGraph, place, parcel.place);
        pickingUp = true;
      } else {
        route = findRoute(roadGraph, place, parcel.address);

yitonghe00

countSteps = (state, robot, memory) => {
  for (let turn = 0;; turn++) {
    if (state.parcels.length == 0) {
      return turn;
    }
    let action = robot(state, memory);
    state = state.move(action.direction);
    memory = action.memory;
  }
}

yitonghe00

let map = {one: true, two: true, hasOwnProperty: true};

// Fix this call
console.log(Object.prototype.hasOwnProperty.call(map, "one"));
// → true

yitonghe00

// Your code here (and the code from the previous exercise)
class GroupIterator {
  constructor(group) {
    this.group = group;
    this.i = 0;
  }
  
  next() {
    if (this.i === this.group.values.length) {
      return { done: true };

yitonghe00

class Group {
  // Your code here.
  constructor() {
    this.values = [];
  }
  
  add(elem) {
    if (!this.has(elem)) {
      this.values.push(elem);
    }

yitonghe00

// Your code here.
class Vec {
  constructor(x, y) {
    this.x = x;
    this.y = y;
  }
 
  plus(parameter) {
    return new Vec(this.x + parameter.x, this.y + parameter.y);
  }

yitonghe00

function dominantDirection(text) {
  // Your code here.
  const directions = countBy(text, (char) => {
  	const script = characterScript(char.codePointAt(0));
    return script ? script.direction : 'none';
  }).filter(({ name }) => name != 'none');

  if (directions.length < 2) return directions[0].name;
  return directions.reduce((a, b) => a.count > b.count ? a.name : b.name);
}

yitonghe00

/*
function every(array, test) {
  // Your code here.
  for (let elem of array) {
    if (!test(elem)) return false;
  }
  return true;
}
*/

yitonghe00

// Your code here.
const loop = (init, test, next, body) => {
  for (let i = init; test(i); i = next(i)) {
    body(i);
  }
};

loop(3, n => n > 0, n => n - 1, console.log);
// → 3
// → 2