Как се добавя калкулатор
<form name="calculator"><input type="button" value="1" /> <input type="button" value="2" /> <input type="button" value="3" /> <input type="button" value="+" /> <input type="button" value="4" /> <input type="button" value="5" /> <input type="button" value="6" /> <input type="button" value="-" /> <input type="button" value="7" /> <input type="button" value="8" /> <input type="button" value="9" /> <input type="button" value="*" /> <input type="button" value="/" /><input type="button" value="0" /> <input type="reset" value="Изчисти" /> <input type="button" value="=" /> Отговор <input name="ans" type="textfield" value="" /> </form>