Euro 2020 Sweepstakes Generator

euroSweepstakes.js

const countries = [
    '🇦🇹  Austria', '🇧🇪  Belgium', '🇭🇷  Croatia', '🇨🇿  Czech Republic', '🇩🇰  Denmark',
    '🏴󠁧󠁢󠁥󠁮󠁧󠁿  England', '🇫🇮  Finland', '🇫🇷  France', '🇩🇪  Germany', '🇭🇺  Hungary',
    '🇮🇹  Italy', '🇳🇱  Netherlands', '🇲🇰  North Macedonia', '🇵🇱  Poland',
    '🇵🇹  Portugal', '🇷🇺  Russia', '🏴󠁧󠁢󠁳󠁣󠁴󠁿  Scotland', '🇸🇰  Slovakia', '🇪🇸  Spain',
    '🇸🇪  Sweden', '🇨🇭  Switzerland', '🇹🇷  Turkey', '🇺🇦  Ukraine', '🏴󠁧󠁢󠁷󠁬󠁳󠁿  Wales'
];

const runSweepstake = () => {
    const contenders = process.argv.slice(2);
    const output = contenders.map(name => {
        return {
            name,
            countries: []
        };
    });

    while (countries.length) {
        shuffle(output);
        output.forEach((_o, index) => {
            const randomCountry = countries[Math.floor(Math.random() * countries.length)];
            if (randomCountry) {
                output[index].countries.push(randomCountry);
                countries.splice(countries.indexOf(randomCountry), 1);
            }
        });
    }

    output.forEach(o => {
        console.log(`${o.name} has drawn: ${o.countries.join(', ')}`)
    });
};

const shuffle = (array = []) => {
    let currentIndex = array.length,
        randomIndex;
  
    while (0 !== currentIndex) {
        randomIndex = Math.floor(Math.random() * currentIndex);
        currentIndex--;
        [array[currentIndex], array[randomIndex]] = [
            array[randomIndex], array[currentIndex]
        ];
    }
  
    return array;
};

runSweepstake();

To run: node euroSweepstakes.js Name1 Name2 Name3 Name4