function solve(params) {
    let partyIndex = params.indexOf('PARTY');
    let guestList = params.slice(0, partyIndex);
    let commingList = params.slice(partyIndex + 1);

    let map = new Map();
    map.set('vip', []);
    map.set('regular', []);

    guestList.forEach(g => Number.isInteger(+g[0]) ?
        map.get('vip').push(g) : map.get('regular').push(g))

    for (let guest of commingList) {
        let index = map.get('vip').indexOf(guest);

        if (index !== -1) {
            map.get('vip').splice(index, 1);
        } else {
            index = map.get('regular').indexOf(guest);
            if (index !== -1) {
                map.get('regular').splice(index, 1);
            }
        }
    }

    let count = map.get('vip').length + map.get('regular').length;
    console.log(count);

    for(let [type,list] of map){
        console.log(list.join('\n'));
    }
}