text: const express = require('express')
  const bodyParser= require('body-parser')
  const app = express()
  app.use(bodyParser.urlencoded({extended: true}));
  const port = 4000
  
  app.get('/', (req,res) => {
  res.sendFile(__dirname + '/index.html')
  })
  
  app.post('/',(req,res)=>{
    var weight= Number(req.body.first);
    var height= Number(req.body.second);
    var bmi= weight/(Math.pow(height,2));
    
   res.send("<h1>Your BMI is: </h1>"+ bmi)
   
   res.redirect('/')
  })
  
  app.listen(port, () => {
    console.log(`Example app listening at http://localhost:${port}`)
  })
  