AoC 2021 day 15 part 2 Node.js

"use strict";
const { Heap } = require('heap-js');
var fs = require("fs");

let t = Date.now();

var file =__filename.slice(__dirname.length + 1, -3)+ ".txt";
let data = fs.readFileSync(file, 'utf8').toString().split('\n').map(s => s.trim());

let grid = data.join("").split('');

let GRIDSIZE =Math.sqrt(grid.length);
let MULTIPLIER = 5;
let endX = GRIDSIZE*MULTIPLIER-1;
let endY = GRIDSIZE*MULTIPLIER-1;
let neighbors = [[-1,0],[1,0],[0,-1],[0,1]];

class Node {
  constructor() {
   this.x=0;
   this.y=0;

   this.f = 0; // g+h;
   this.g = 9999; // cost so far
   this.h = 0; // distance to goal
   this.inOpen = false;
   this.isClosed = false;
  }
};

let  graph = {
  nodes:[],
  openList: new Heap((a,b) => a.g - b.g)
};


function getNode( x,  y){
  if(graph.nodes[x+"_"+y] == undefined)
  {
    let n = new Node();
    n.x = x;
    n.y = y;
    n.h = (endX - x) + (endY - y);
    graph.nodes[x+"_"+y]= n;
  }
  return graph.nodes[x+"_"+y];
}

let n = getNode(0,0);
n.inOpen = true;
n.g = 0;
graph.openList.push(n)
let destination = false;

while (destination == false){
  let n = graph.openList.pop();
  if (n.x == endX && n.y == endY){
    destination = true;
    console.log("DONE!!!!");
    console.log(n.g);
  }
  else{

    n.inOpen = false;

    for (let edge of neighbors){

      let x = n.x+edge[0];
      let y = n.y+edge[1];
      if(x<0 || x>endX || y<0 || y>endY)
        continue;

      let n2 = getNode(x,y);

      if(n2.isClosed)
        continue;

      let oX = x % GRIDSIZE;
      let oY = y % GRIDSIZE;
      let gX = Math.floor(x / GRIDSIZE);
      let gY = Math.floor(y / GRIDSIZE);

      let gg = Number(grid[oY*GRIDSIZE + oX]) + gX + gY;

      if(gg>9){
        gg -= 9;
      }

      let g = n.g + gg;

      if( !n2.inOpen ){
        n2.g = g;
       // n2.f = g;
        n2.inOpen = true;

        graph.openList.push(n2);
      }else if (n2.g > g){
        n2.g = g;
      //  n2.f = g;
      }

    }
  }
  n.isClosed = true;
}

console.log("----------------------");
console.log(Date.now()-t);