function solve() {


    document.getElementsByTagName('button')[0].addEventListener('click', () => {
        event.preventDefault();
        let userName = document.querySelectorAll(".user-info input[type=text]")[0].value;
        let userEmail = document.querySelectorAll(".user-info input[type=text]")[1].value;
        let userPassword = document.querySelector(".user-info input[type=password]").value;
        let chks = Array.from(document.querySelectorAll("input[type='checkbox']:checked")).map(p => p.value);

        let table = document.getElementsByTagName('table')[0].getElementsByTagName('tbody')[0];
        let row = document.createElement('tr');
        let name = document.createElement('td');
        name.innerHTML = userName;
        let email = document.createElement('td');
        email.innerHTML = userEmail;
        let topics = document.createElement('td');
        topics.innerHTML = chks.join(' ');
        row.appendChild(name);
        row.appendChild(email);
        row.appendChild(topics);
        table.appendChild(row);

    })
    document.getElementsByTagName('button')[1].addEventListener('click', () => {
        event.preventDefault();
        let searchedString = document.querySelectorAll("input[type='text']")[2].value;
        let tds = Array.from(document.querySelectorAll('table tbody tr td'));
        console.log(tds);

        for (const td of tds) {
            td.parentNode.style.visibility = 'hidden';
        }
        for (const td of tds) {
            if (td.textContent.includes(searchedString)) {
                td.parentNode.style.visibility = 'visible';
            }

        }
    })

}