content: import React, { Component } from 'react';
  import { render } from 'react-dom';
  import Clock from './Clock';
  import Perf from 'react-addons-perf';
  
  class App extends Component {
    constructor(){
      super(...arguments);
      this.state = this.getTime();
    }
  
    componentDidMount(){
      setInterval(()=>{
        this.setState(this.getTime());
      },10);
    }
  
    getTime(){
      let now = new Date();
      return {
        hours: now.getHours(),
        minutes: now.getMinutes(),
        seconds: now.getSeconds(),
        tenths: parseInt(now.getMilliseconds()/10),
      };
    }
  
    render(){
      let clocks=[];
      for (var i = 0; i < 200; i++) {
        clocks.push(<Clock hours={this.state.hours} minutes={this.state.minutes} seconds={this.state.seconds} tenths={this.state.tenths} />)
      }
  
      return (
        <div>
          {clocks}
        </div>
      );
    }
  }
  
  Perf.start()
  render(<App />, document.getElementById("root"));
  setTimeout(()=>{
    Perf.stop();
    Perf.printWasted();
  },2000)
  