Project Euler #011

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

package {
    import flash.display.Sprite;
    import flash.text.TextField;
    
    public class ProjectEuler extends Sprite {
		private var _textField:TextField;
       
        public function ProjectEuler() {
        		initialize();
        		writeAnswer(new Problem011);
        }
        
        private function writeAnswer(problem:AbstructProblem):void {
        		var answer:String = problem.getAnswer();
        		 _textField.appendText(answer);
        }
        
        private function initialize():void {
        	    _textField = new TextField();
            _textField.width = stage.stageWidth;
            _textField.height = stage.stageHeight;
            addChild(_textField);
        }
    }
}

class AbstructProblem {
	final public function getAnswer():String {
		var answer:String;
		try {
			answer = solve().toString();
		} catch (err:Error) {
			answer = err.name + " : " + err.message;
		}
		return answer;
	}
	
	protected function solve():Number {
		throw new Error("unsolved");
	}
}

class Problem011 extends AbstructProblem {
	override protected function solve():Number {
		var answer:Number=0;
		
		const size:uint = 20;
		const numChain:uint = 4;
		var data:String = "08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08 " + 
						  "49 49 99 40 17 81 18 57 60 87 17 40 98 43 69 48 04 56 62 00 " + 
						  "81 49 31 73 55 79 14 29 93 71 40 67 53 88 30 03 49 13 36 65 " + 
						  "52 70 95 23 04 60 11 42 69 24 68 56 01 32 56 71 37 02 36 91 " + 
						  "22 31 16 71 51 67 63 89 41 92 36 54 22 40 40 28 66 33 13 80 " + 
						  "24 47 32 60 99 03 45 02 44 75 33 53 78 36 84 20 35 17 12 50 " + 
						  "32 98 81 28 64 23 67 10 26 38 40 67 59 54 70 66 18 38 64 70 " + 
						  "67 26 20 68 02 62 12 20 95 63 94 39 63 08 40 91 66 49 94 21 " + 
						  "24 55 58 05 66 73 99 26 97 17 78 78 96 83 14 88 34 89 63 72 " + 
						  "21 36 23 09 75 00 76 44 20 45 35 14 00 61 33 97 34 31 33 95 " + 
						  "78 17 53 28 22 75 31 67 15 94 03 80 04 62 16 14 09 53 56 92 " + 
						  "16 39 05 42 96 35 31 47 55 58 88 24 00 17 54 24 36 29 85 57 " + 
						  "86 56 00 48 35 71 89 07 05 44 44 37 44 60 21 58 51 54 17 58 " + 
						  "19 80 81 68 05 94 47 69 28 73 92 13 86 52 17 77 04 89 55 40 " + 
						  "04 52 08 83 97 35 99 16 07 97 57 32 16 26 26 79 33 27 98 66 " + 
						  "88 36 68 87 57 62 20 72 03 46 33 67 46 55 12 32 63 93 53 69 " + 
						  "04 42 16 73 38 25 39 11 24 94 72 18 08 46 29 32 40 62 76 36 " + 
						  "20 69 36 41 72 30 23 88 34 62 99 69 82 67 59 85 74 04 36 16 " + 
						  "20 73 35 29 78 31 90 01 74 31 49 71 48 86 81 16 23 57 05 54 " + 
						  "01 70 54 71 83 51 54 69 16 92 33 48 61 43 52 01 89 19 67 48";
		var grid:Vector.<uint> = new Vector.<uint>();
		
		for each (var str:String in data.split(' ')) {
			grid.push(parseInt(str));
		}
		
		var mul_tate:uint;
		var mul_yoko:uint;
		var mul_naname1:uint;
		var mul_naname2:uint;
		var mul_max:uint;
		for (var x:uint=0; x < size - numChain; x++) {
			for (var y:uint=0; y < size - numChain; y++) {
				mul_tate = 1;
				mul_yoko = 1;
				mul_naname1 = 1;
				mul_naname2 = 1;
				
				for (var i:uint=0; i < numChain; i++) {
					mul_tate *= grid[y*size + x + i];
					mul_yoko *= grid[(y+i)*size + x];
					mul_naname1 *= grid[(y+i)*size + x + i];
					mul_naname2 *= grid[(y+numChain-i)*size + x + i];
				}
				
				mul_max = Math.max(Math.max(mul_tate, mul_yoko), Math.max(mul_naname1, mul_naname2));
				
				if (answer < mul_max) {
					answer = mul_max;
				}
			}
		}
		
		return answer;
	}

}

class Utils {
	// 整数値の桁数の取得
	static public function disits(n:Number, radix:uint=10):Number {
		var d:Number = 0;
		
		n = Math.abs(n);
		while (n / radix != 0) {
			n = Math.floor(n / radix);
			d++;
		}
		
		return d;
	}
	
	// 指定した桁の値を取得
	static public function numberAt(n:Number, digit:Number, radix:Number=10):Number {
		var number:Number;
		
		while (--digit) {
			n = Math.floor(n / radix);
		}
		
		return n % radix
	}
	
	// 素数を列挙
	static public function getPrimeList(limit:uint):Vector.<uint> {
		var sequence:Vector.<uint> = new Vector.<uint>(limit);
		
		for (var i:uint = 2; i < limit; i++) {
			sequence[i] = i;
		}
		
		for (i=2; i < limit; i++) {
			if (sequence[i]) {
				for (var j:uint = i+i; j < limit; j+=i) {
					sequence[j] = 0;
				}
			}
		}
		
		var primeList:Vector.<uint> = new Vector.<uint>();
		for (i=2; i < limit; i++) {
			if (sequence[i]) {
				primeList.push(i);
			}
		}
		
		return primeList;
	}
}