Examle vdom in react

myApp.js

import React, { Component } from "react";
import "./App.css";

class example extends Component {
  constructor(props) {
    super(props);
    this.state = { data: 0 };

    this.run = this.run.bind(this);
  }

  run() {
    this.setState(state => ({
      data: (this.state.data += 1)
    }));
  }
  render() {
    return (
      <div className="App">
        <header className="App-header">
          <h1>React VDOM</h1>
          <div class="row">
            <p class="le">number:{this.state.data}</p>
            <p class="ri"></p>
          </div>
          <button class="mbutton" onClick={this.run}>
            Hit me
          </button>
        </header>
      </div>
    );
  }
}

export default example;