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<p id="demo"></p>
<p id="myList">This is my text</p>
// first way of accessing element
document.getElementById("demo").innerHTML = "I have changed!";
// second way of accessing element
var element=document.getElementById("demo");
element.innerHTML = "I have changed!";
// get text of id myList
let html = document.getElementById("myList").innerHTML;
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var out = document.getElementById("out");
var res = out.innerHTML;
res = "foo";