text: 
  const  match = ["",null,0] 
  
  const price = {
          A4          : 25,
          A4_pass     : 50,
          A4_back     : 30,
          legal       : 30,
          legal_back  : 40,
          A3          : 60,
          A3_back     : 120
  }
  const record = {
          A4          : 0,
          A4_back     : 0,
          legal       : 0,
          legal_back  : 0,
          A3          : 0,
          A3_back     : 0
  
  }
  const Show = element => {
      return element.style.display = "grid "
  }
  const Hide = element => {
      return element.style.display = "none"
  }
  const calculate_total = () => {
  
      let all = 0
      for( let name in record){
          all += record[name]
      }
      
      return document.getElementById("total_price_all").value   = all
  }
  
  const getValue = (item) => {
      
      amount                    = Number(document.getElementById(item).value)
      items = document.getElementById(item+"_item")
      console.log(items)
      
      if(match.includes(amount) !== true){
          Show(items)
          document.getElementById(item+"_amount").textContent = amount
          total_price  = amount * price[item]
          document.getElementById(item+"_total_price").value  = total_price
          record[item] = total_price
      }
      else {
          Hide(items)
          record[item] = 0
      }   
      calculate_total()
      
  }
  const changePrice = (price,item) => {
      
      new_price                                          = Number(document.getElementById(item).value) * Number(price)
      document.getElementById(item+"_total_price").value = new_price
      record[item]                                       = new_price
      calculate_total()
  
  
  }
  