将此Jquery函数重写为普通Javascript

$(document).ready(function(){
    $("button").click(function(){
        $("p").hide();
    });
});

document.addEventListener("DOMContentLoaded", function(){
    var buttons = document.getElementsByTagName("button");
    for (var i = 0; i < buttons.length; i++) {
        buttons[i].addEventListener("click", function(){
            var paragraphs = document.getElementsByTagName("p");
            for (var j = 0; j < paragraphs.length; j++) {
                paragraphs[j].style.display = "none";
            }
        });
    }
});