JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://files.cnblogs.com/jscode/diff_match_patch.js"></script>
<div class="test">
        <div id="oldStr" class="text">the stackoverflow question and answer version control is very well,i want to do this use javascript,but i don't know how to start,who can give some suggestion?thanks</div>
        <div id="newStr" class="text">Stack Overflow's diff view is very good. I want to do this using  javascript,but i don't know how to start,who can give some suggestion?thanks</div>
    </div>
    <input type="button" value="Test" onclick="launch()" />
    <div class="test">
        <div class="text" id="outputOldStr"></div>
        <div class="text" id="outputNewStr"></div>
    </div>

CSS

.test
        {
            margin:10px 0;
            zoom:1;
        }
        .test:after
        {
            height:0;
            clear:both;
            content:"";
            visibility:hidden;
            display:block;
        }
        .text
        {
            width:300px;
            float:left;
            margin-right:10px;
            border:1px solid #F60;
            padding:10px;
            min-height:80px;
        }
        .text-del
        {
            text-decoration: line-through;
            color: #A82400;
            background-color: #E5BDB2;
        }
        .text-add
        {
            background: #D1E1AD;
            color: #405A04;
        }

JavaScript

var dmp = new diff_match_patch();

function launch() {
    var text1 = document.getElementById('oldStr').innerHTML;
    var text2 = document.getElementById('newStr').innerHTML;
    dmp.Diff_EditCost = 8;

    var d = dmp.diff_main(text1, text2);
    dmp.diff_cleanupEfficiency(d);
    var oldStr = "",
        newStr = "";
    for (var i = 0, j = d.length; i < j; i++) {
        var arr = d[i];
        if (arr[0] == 0) {
            oldStr += arr[1];
            newStr += arr[1];
        } else if (arr[0] == -1) {
            oldStr += "<span class='text-del'>" + arr[1] + "</span>";
        } else {
            newStr += "<span class='text-add'>" + arr[1] + "</span>";
        }
    }
    document.getElementById('outputOldStr').innerHTML = oldStr;
    document.getElementById('outputNewStr').innerHTML = newStr;
}