Generuje tabliczkę mnożenia/dzielenia do 50, po 18 w słupku. Wymagany node

generujTabliczke_xD.js

#! /usr/bin/env node

//Generuje tabliczkę mnozenia/dzielenia w dwoch kolumnach, do 50, po 18 w slupku
//Wymagany: node
//uruchomienie: ./generujTabliczke_xD.js >> tabliczka (wrzuci tabliczke do pliku "tabliczka")
// 2 * 9 = ___        16 : 2 = ___
// 9 * 1 = ___        35 : 7 = ___
// 5 * 6 = ___        30 : 3 = ___
// 7 * 4 = ___        5 : 5 = ___
// 9 * 6 = ___        45 : 5 = ___
// 2 * 2 = ___        18 : 9 = ___
// 2 * 3 = ___        24 : 8 = ___
// 2 * 6 = ___        40 : 8 = ___
// 1 * 6 = ___        15 : 3 = ___
// 1 * 3 = ___        10 : 10 = ___
// 1 * 2 = ___        50 : 5 = ___
// 3 * 7 = ___        24 : 6 = ___
// 9 * 4 = ___        8 : 8 = ___
// 1 * 1 = ___        42 : 7 = ___
// 4 * 3 = ___        27 : 3 = ___
// 8 * 4 = ___        7 : 1 = ___
// 7 * 2 = ___        40 : 10 = ___
// 8 * 6 = ___        18 : 6 = ___

const randomInt = max => Math.round(Math.random() * max);
const randomPair = max => {
  const first = randomInt(max);
  const second = randomInt(
    Math.min(max, (max + Math.floor(max/2)) - first)
  )
  
  return [first, second];
}

const ifLastThreeContainPair = (pair, list) => {
  let i = list.length - 1;
  while (i > 0) {
    const e = list[i];
    if (
      e[0] == pair[0] && e[1] == pair[1] ||
      e[0] == pair[1] && e[1] == pair[0]
    ) {
      return true;
    }
    i--;
  }
  return false;
}

const generateList = (max, amount) => {
  const arr = [];
  
  while(arr.length < amount) {
    const pair = randomPair(max);

    if (pair[0] && pair[1] && !ifLastThreeContainPair(pair, arr)) {
      arr.push(pair);      
    }
  }
  
  return arr;
}

const createMultiply = pair => `${pair[0]} * ${pair[1]} = ___`;
const createDivision = pair => {
  const result = pair[0] * pair[1];
  if (Math.random() >= 0.5) {
    return `${result} : ${pair[0]} = ___`;
  } else {
    return `${result} : ${pair[1]} = ___`;
  }
}
const space = "        ";
const br = "\n";

let str = "";

const list = generateList(10, 36);

list.forEach((el, idx) => {
  if (idx % 2 > 0) {
    str += createDivision(el);
    str += br;
  } else {
    str += createMultiply(el);
    str += space;    
  }
});

console.log(str);