blockchain_dev_pass.js

var hashVal = (sha256 hash value of "blockchain dev")
// HINT: hashVal.substring(0,4) === "6d1c"
var pattern = /((?=e{2})[0-9]{2})|([2468]{2})|([0-9]{1,3})(?=[a-d])/g
var matches = (Get matched string array of hashVal by using pattern)
// HINT : matches[11] === "1"
var d = new Date()
var dateVal = d.getYear() * (d.getMonth()+1) * 100
// HINT : If room master forgot to update password monthly, try previous one
var compress = function(input) {
  var cb = function(a,b){return parseInt(a)+parseInt(b)}
  return (calculate reduced value of input array by using above cb as callback function and dateVal as initialValue)
  // HINT : Array.prototype.reduce()
}
var password = compress(matches)
console.log(password)