[Areso]

<script>
       function Calc()
    {
        
       var priceitem = Number(document.getElementById('priceitem').value)
         
       alert (priceitem)
         
       var priceenchant = Number(document.getElementById('priceenchant').value)
     
       alert (priceenchant)
         
       var basicchance = Number(document.getElementById('basicchance').value)
        
       alert (basicchance)
         
       var safetyenchant = Number(document.getElementById('safetyenchant').value)
        
       alert (safetyenchant)
         
       var levelenchant = Number(document.getElementById('levelenchant').value)
        
       alert (levelenchant)
         
       var sum=0
       var sumpriceitem = 0
        
        if ((levelenchant >= 0) && (levelenchant<=20))
        {
            if ((basicchance >=1) && (basicchance<=100))
            {
            if (levelenchant > safetyenchant)
               {
                for (i=1; levelenchat-safetyenchant; i++)
                {
                sum = sum + (1 - (basicchance / 100) ^ i) * priceitem
                }
               }
            sumpriceitem = priceitem + priceenchant * levelenchant + sum
            document.getElementById('summary').value = sumpriceitem
            }
            else
            {
            alert=("Chance of successful enchant incorrect. Please, re-enter chance of enchant from 1 to 100")
            }
        }
        else
        {
        alert=("Level of enchant incorrect. Please, re-enter level of enchant from 0 to 20")
        }
    }
    </script>

К сожалению, не работает.