hbsv,
Вот ваш калькулятор с выброшенным лишним и небольшими добавлениями
<!DOCTYPE html>
<html>
<head>
<title>Calc</title>
<script type="text/javascript">
var calcString = "";
function kalk() {
var res = eval(calcString);
document.getElementById("res").innerHTML = calcString + "=" + res;
}
function addToInput(value) {
calcString += value;
document.getElementById("res").innerHTML = calcString;
}
function clean() {
calcString = "";
document.getElementById("res").innerHTML = calcString;
}
</script>
</head>
<body>
<table>
<tr>
<td>
<div id="res" style="width:400px;height:20px;border:solid 1px black;">
</div>
</td>
</tr>
<tr>
<td class="buttons">
<div id="num1" align="center">
<input type="button" onclick="addToInput(this.value)" name="rakam11" value="1" />
<input onclick="addToInput(this.value)" type="button" name="rakam22" value="2" />
<input onclick="addToInput(this.value)" type="button" name="rakam33" value="3" />
<input onclick="addToInput(this.value)" type="button" name="rakam44" value="4" />
<input onclick="addToInput(this.value)" type="button" name="rakam55" value="5" />
<input onclick="addToInput(this.value)" type="button" name="rakam66" value="6" />
<input onclick="addToInput(this.value)" type="button" name="rakam77" value="7" />
<input onclick="addToInput(this.value)" type="button" name="rakam88" value="8" />
<input onclick="addToInput(this.value)" type="button" name="rakam99" value="9" />
<input onclick="addToInput(this.value)" type="button" name="rakam00" value="0" />
</div>
<div id="act" align="center">
<input onclick="addToInput(this.value)" type="button" name="plus" value="+" />
<input onclick="addToInput(this.value)" type="button" name="minus" value="-" />
<input onclick="addToInput(this.value)" type="button" name="umn" value="*" />
<input onclick="addToInput(this.value)" type="button" name="delit" value="/" />
</div>
<tr>
<td colspan="2"><input type="button" name="button" id="button" onclick="kalk()" value="Считать" />
<input type="button" name="button1" onclick="clean()" value="CLEAN" /></td>
</tr>
</table>
</body>
</html>
Можно еще добавить кнопки с точкой, скобками, DEL - удаление посимвольно с конца