function solve() {
    const inputField = document.getElementsByTagName('input')[0];
    let list = document.getElementsByTagName('li');

    document
        .getElementsByTagName('button')[0]
        .addEventListener('click', () => {
            let name = inputField.value;

            if (name) {
                let resultName = name[0].toLocaleUpperCase();
                let index = resultName.charCodeAt(0) - 65;
                resultName += name.slice(1);

                if (list[index].textContent.length <= 0) {
                    list[index].textContent += resultName;
                } else {
                    list[index].textContent += ', ' + resultName;
                }

                inputField.value = ''
            }
        })
}