IMO 1962 Problem 01

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 * Copyright _ex_ ( http://wonderfl.net/user/_ex_ )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/wNJc
 */

<?xml version="1.0" encoding="utf-8"?>
<!-- forked from _ex_'s IMO 1960 Problem 01 -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute"
                width="480" height="360" backgroundColor="#FFFFFF" xmlns="*">

    <mx:ApplicationControlBar dock="true" width="100%">
        <mx:Label id="lblProblem" x="10" y="10" width="380" height="140">
            <mx:text>
            <![CDATA[
     IMO 1962 Problem 01
     Find the smallest natural number n which has the following
     properties:

     (a) Its decimal representation has 6 as the last digit.
     (b) If the last digit 6 is erased and placed in front of
         the remaining digits, the resulting number is four
         times as large as the original number n.
            ]]>
            </mx:text>
        </mx:Label>
        <mx:Button id="btnSolve" x="395" y="115" click="solve();" label="Solve!" />
    </mx:ApplicationControlBar>
    <mx:Script>
        <![CDATA[
            public function solve():void {
                txtResult.text = "";

                var k:int = 1;
                var k_up:int = 10;    // Minimum (10^p) greater that k.
                while (true) {
                    var n:int = (10 * k) + 6;
                    var m:int = (6 * k_up) + k;

                    // Check
                    if (m == 4 * n) {
                        txtResult.text += "ANSWER: " + n;
                        break;
                    }
                    ++k;
                    if (k >= k_up) {
                        k_up *= 10;
                    }
                }
            }
        ]]>
    </mx:Script>
    <mx:TextArea id="txtResult" x="5" y="15" width="470" height="190" />

</mx:Application>