깔끔한 다기능 계산기

// 아래의 코드를 원하는 위치에 복사 해 넣으세요

<table border=1 width=50 height=60 cellpadding=1 cellspacing=5>
<form name="Keypad" action="">
        <tr>
                <td colspan=3 align=middle><input name="ReadOut" type="Text" size=24 value="0" width=100%></td>
                <td></td>
                <td><input name="btnClear" type="Button" value="  C  " onclick="Clear()"></td>
                <td><input name="btnClearEntry" type="Button" value="  CE " onclick="ClearEntry()"></td>
        </tr>
        <tr>
                <td><input name="btnSeven" type="Button" value="  7  " onclick="NumPressed(7)"></td>
                <td><input name="btnEight" type="Button" value="  8  " onclick="NumPressed(8)"></td>
                <td><input name="btnNine" type="Button" value="  9  " onclick="NumPressed(9)"></td>
                <td></td>
                <td><input name="btnNeg" type="Button" value=" +/- " onclick="Neg()"></td>
                <td><input name="btnPercent" type="Button" value="  % " onclick="Percent()"></td>
        </tr>
        <tr>
                <td><input name="btnFour" type="Button" value="  4  " onclick="NumPressed(4)"></td>
                <td><input name="btnFive" type="Button" value="  5  " onclick="NumPressed(5)"></td>
                <td><input name="btnSix" type="Button" value="  6  " onclick="NumPressed(6)"></td>
                <td></td>
                <td><input name="btnPlus" type="Button" value="  +  " onclick="Operation('+')"></td>
                <td><input name="btnMinus" type="Button" value="   -   " onclick="Operation('-')"></td>
        </tr>
        <tr>
                <td><input name="btnOne" type="Button" value="  1  " onclick="NumPressed(1)"></td>
                <td><input name="btnTwo" type="Button" value="  2  " onclick="NumPressed(2)"></td>
                <td><input name="btnThree" type="Button" value="  3  " onclick="NumPressed(3)"></td>
                <td></td>
                <td><input name="btnMultiply" type="Button" value="  *  " onclick="Operation('*')"></td>
                <td><input name="btnDivide" type="Button" value="   /   " onclick="Operation('/')"></td>
        </tr>
        <tr>
                <td><input name="btnZero" type="Button" value="  0  " onclick="NumPressed(0)"></td>
                <td><input name="btnDecimal" type="Button" value="   .  " onclick="Decimal()"></td>
                <td colspan=3></td>
                <td><input name="btnEquals" type="Button" value="  =  " onclick="Operation('=')"></td>
        </tr>
</form>
</table>

<script language="JavaScript">
<!--
var FKeyPad = document.Keypad;
var Accum = 0;
var FlagNewNum = false;
var PendingOp = "";

function NumPressed (Num) {
        if (FlagNewNum) {
                FKeyPad.ReadOut.value  = Num;
                FlagNewNum = false;
         }
        else {
                if (FKeyPad.ReadOut.value == "0")
                FKeyPad.ReadOut.value = Num;
                else
                FKeyPad.ReadOut.value += Num;
         }
}
function Operation (Op) {
        var Readout = FKeyPad.ReadOut.value;
        if (FlagNewNum && PendingOp != "=");
        else
        {
        FlagNewNum = true;
        if ( '+' == PendingOp )
        Accum += parseFloat(Readout);
        else if ( '-' == PendingOp )
        Accum -= parseFloat(Readout);
        else if ( '/' == PendingOp )
        Accum /= parseFloat(Readout);
        else if ( '*' == PendingOp )
        Accum *= parseFloat(Readout);
        else
        Accum = parseFloat(Readout);
        FKeyPad.ReadOut.value = Accum;
        PendingOp = Op;
           }
}
function Decimal () {
        var curReadOut = FKeyPad.ReadOut.value;
        if (FlagNewNum) {
        curReadOut = "0.";
        FlagNewNum = false;
           }
        else
        {
        if (curReadOut.indexOf(".") == -1)
        curReadOut += ".";
           }
        FKeyPad.ReadOut.value = curReadOut;
}
function ClearEntry () {
        FKeyPad.ReadOut.value = "0";
        FlagNewNum = true;
}
function Clear () {
        Accum = 0;
        PendingOp = "";
        ClearEntry();
}
function Neg () {
        FKeyPad.ReadOut.value = parseFloat(FKeyPad.ReadOut.value) * -1;
}
function Percent () {
        FKeyPad.ReadOut.value = (parseFloat(FKeyPad.ReadOut.value) / 100) * parseFloat(Accum);
}
//-->
</script>

// 여기까지 입니다
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