Task

task.js

/*
@readyyyk

Write a function that finds way from point "FORM" to point "TO"

function takes 3 args - 
- point "from"
- point "to"
- function "getPaths" that returns places that can be reached from provided point

*/


// getRoutes implemetation
const shuffle=(s)=>s.sort(_=>0.5-Math.random());
let letters = ["x","y","z","A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"];
const getRoutes = () => {
  const n = Math.floor(Math.random()*Math.min(6, letters.length));
  let r = [];
  for (let i = 0; i < n; i++){
    letters = shuffle(letters);
    r.push(letters.shift());
  }
  return r;
}


/* solve */
const updatePaths = (oldPaths, available) => available.length ? oldPaths.map(el=>available.reduce(
  (acc, cur) => [...acc, [...el, cur]], [])).flat() : oldPaths;

const findPath = (from, to, _getRoutes) => {
  letters = letters.sort(el=>el!==to);
  const stack = [from];
  const visited = [from];
  let paths = [[from]];

  let cnt = 0;

  while(stack.length) {
    cnt++;

    const cur = stack.shift();
    const available = _getRoutes(cur);

    if(available.includes(to)) {
      return [cnt, [...paths.find(el=>paths.at(-1) == el), to]];
    }
    
    paths = updatePaths(paths, available);

    stack.push(...available.filter(el=>!(el in visited)));
  }

  return [cnt, new Error("No way")];
}

const [cnt, res] = findPath("A", "B", getRoutes);

console.log(cnt, res)