solve.js

module.exports = function solve(maze, miner, exit) {
  let directionsArray = ["up", "right", "down", "left"];
  const movements = {
    left: { x: -1, y: 0 },
    right: { x: 1, y: 0 },
    up: { x: 0, y: -1 },
    down: { x: 0, y: 1 }
  };

  const xNum = maze.length;
  const yNum = maze[0].length;
  const xTarget = exit.x;
  const yTarget = exit.y;
  const path = [];
  const visited = [];

  for (let x = 0; x < xNum; ++x) {
    visited.push([]);
    for (let y = 0; y < yNum; ++y) {
      visited[x].push(false);
    }
  }

  function dfs(x, y) {
    if (x == xTarget && y == yTarget) {
      return true;
    }

    for (let i = 0; i < directionsArray.length; ++i) {
      let delta = movements[directionsArray[i]];
      x += delta.x;
      y += delta.y;
      if (
        x < xNum &&
        y >= 0 &&
        x >= 0 &&
        y < yNum &&
        !visited[x][y] &&
        maze[x][y]
      ) {
        path.push(directionsArray[i]);
        visited[x][y] = true;
        if (dfs(x, y)) {
          return true;
        }
        visited[x][y] = false;
        path.pop();
      }
      x -= delta.x;
      y -= delta.y;
    }
    return false;
  }
  visited[miner.x][miner.y] = true;
  dfs(miner.x, miner.y);
  return path;
};