function splitIntoChunks(str, chunkSize) {
  let chunks = [];

  for (let i = 0; i < str.length; i += chunkSize) {
    let chunk = str.slice(i, i + chunkSize);
  }
  return chunks;
}

function baseLog(x, y) {
  return Math.log(y) / Math.log(x);
}

function stringToNumber(string, bool) {
  var str = string;
  let num = BigInt(0);
  for (let i = 0; i < str.length; i++) {
    num = num * BigInt(1103871) + BigInt(str.charCodeAt(i));
  }
  if (bool) {
    console.log(string);
    console.log(numberToString(num, false));
  }
  return num;
}

function numberToString(number, bool) {
  let str = '';
  var num = number;
  while (num > 0) {
    let charCode = Number(num % BigInt(1103871));
    str = String.fromCharCode(charCode) + str;
    num = num / BigInt(1103871);
  }
  if (bool) {
    console.log(number);
    console.log(stringToNumber(str, false));
  }
  return str;
}

function encode(string) {
  var encodedString = encodeURIComponent(string);
  var array = encodedString.split("");
  var newNumberArray = [];
  array.forEach(char => {
    newNumberArray.push(JSON.stringify(10 + char.charCodeAt(0)));
  })
  return encodeURIComponent(numberToString(BigInt(parseInt(newNumberArray.join(""))), true));
}

function decode(string) {
  var weirdUnicodeCharacters = decodeURIComponent(string);
  var jumbledArray = splitIntoChunks(stringToNumber(weirdUnicodeCharacters, true).toString(), 2);
  var resultString = "";
  jumbledArray.forEach(num => {
    resultString = resultString + String.fromCharCode(parseInt(num) - 10);
  })
  return resultString;
}

/* Usage:
encode(str);
decode(str);
*/

// Testing: 
console.log(encode("Hello world!"));
console.log(decode(encode("Hello world!")));