Intcode.js

const list = [
  1, 12, 2, 3, 1, 1, 2, 3, 1, 3, 4, 3, 1, 5, 0, 3, 2, 1, 9, 19, 1, 19, 5, 23, 2,
  23, 13, 27, 1, 10, 27, 31, 2, 31, 6, 35, 1, 5, 35, 39, 1, 39, 10, 43, 2, 9,
  43, 47, 1, 47, 5, 51, 2, 51, 9, 55, 1, 13, 55, 59, 1, 13, 59, 63, 1, 6, 63,
  67, 2, 13, 67, 71, 1, 10, 71, 75, 2, 13, 75, 79, 1, 5, 79, 83, 2, 83, 9, 87,
  2, 87, 13, 91, 1, 91, 5, 95, 2, 9, 95, 99, 1, 99, 5, 103, 1, 2, 103, 107, 1,
  10, 107, 0, 99, 2, 14, 0, 0,
];
const chunkSize = 4;

const makeChunkedList = (arr, chunkSize) => {
  const returnArr = [];
  for (let i = 0, len = arr.length; i < len; i += chunkSize)
    returnArr.push(arr.slice(i, i + chunkSize));
  return returnArr;
};

function processArray(list) {
  const updatedList = makeChunkedList(list, 4);
  for (let i = 0; i < updatedList.length; i++) {
    if (updatedList[i][0] === 99) {
      list[0] = updatedList[i - 1][3];
      updatedList[0][0] = updatedList[i - 1][3];
      break;
    } else {
      if (updatedList[i][0] === 1) {
        list[(i + 1) * 4 - 1] =
          list[updatedList[i][1]] + list[updatedList[i][2]];
        updatedList[i][3] = list[updatedList[i][1]] + list[updatedList[i][2]];
      } else if (updatedList[i][0] === 2) {
        list[(i + 1) * 4 - 1] =
          list[updatedList[i][1]] * list[updatedList[i][2]];
        updatedList[i][3] = list[updatedList[i][1]] * list[updatedList[i][2]];
      }
    }
  }
  return list[0];
}

function findOtherTwos(list) {
  for (let i = 0; i < 100; i++) {
    for (let j = 0; j < 100; j++) {
      list[1] = j;
      list[2] = i;
      let output = processArray(list);
      if (output === 19690720) {
        console.log(`For output ${output} the two inputs are ${j} and ${i}`);
        console.log(100 * j + i);
        break;
      }
    }
  }
}

let finalResult = processArray(list);
console.log("Final result is: ", finalResult);

findOtherTwos(list);