function solve() {
    let buttons = Array.from(document.getElementsByTagName('button'));
    buttons[0].addEventListener('click', function () {
        let num = document.getElementById('input').value;
        let selectToVal = document.getElementById('selectMenuTo').value;
        if (selectToVal === 'binary') {
            document.getElementById('result').value = (+num).toString(2);
        } else if(selectToVal === 'hexadeicmal') {
            document.getElementById('result').value = (+num).toString(16);
        }
    });
}