#!/usr/bin/env js

function dblSize(){
    var pElements = document.getElementsByTagName("p");
    if (pElements.length == 0) {
	alert('p要素が存在しません。');
    }else{
	for (let i of pElements){
	    i.style.fontSize ='200%';
	}
    }
}
document.addEventListener("DOMContentLoaded",function(e){
    document.body.addEventListener("click",dblSize);
});