Sudoku creator/solver with AS3

package {
	import flash.display.Sprite;
	import flash.text.*;
	public class sudoku extends Sprite {
		public function sudoku() {
			var sudoku = new Array(0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0);
			solve(sudoku);
		}
		function return_row(cell) {
			return Math.floor(cell / 9);
		}
		function return_col(cell) {
			return cell % 9;
		}
		function return_block(cell) {
			return Math.floor(return_row(cell) / 3) * 3 + Math.floor(return_col(cell) / 3);
		}
		function is_possible_row(number,row,sudoku) {
			var possible = true;
			for (var i=0; i<=8; i++) {
				if (sudoku[row*9+i] == number) {
					possible = false;
					break;
				}
			}
			return possible;
		}
		function is_possible_col(number,col,sudoku) {
			var possible = true;
			for (var i=0; i<=8; i++) {
				if (sudoku[col+9*i] == number) {
					possible = false;
					break;
				}
			}
			return possible;
		}
		function is_possible_block(number,block,sudoku) {
			var possible = true;
			for (var i=0; i<=8; i++) {
				if (sudoku[Math.floor(block/3)*27+i%3+9*Math.floor(i/3)+3*(block%3)] == number) {
					possible = false;
					break;
				}
			}
			return possible;
		}
		function is_possible_number(cell,number,sudoku) {
			var row = return_row(cell);
			var col = return_col(cell);
			var block = return_block(cell);
			return is_possible_row(number,row,sudoku) && is_possible_col(number,col,sudoku) && is_possible_block(number,block,sudoku);
		}
		function is_correct_row(row,sudoku) {
			var right_sequence = new Array(1,2,3,4,5,6,7,8,9);
			var row_temp= new Array();
			for (var i=0; i<=8; i++) {
				row_temp[i] = sudoku[row*9+i];
			}
			row_temp.sort();
			return row_temp.join() == right_sequence.join();
		}
		function is_correct_col(col,sudoku) {
			var right_sequence = new Array(1,2,3,4,5,6,7,8,9);
			var col_temp= new Array();
			for (var i=0; i<=8; i++) {
				col_temp[i] = sudoku[col+i*9];
			}
			col_temp.sort();
			return col_temp.join() == right_sequence.join();
		}
		function is_correct_block(block,sudoku) {
			var right_sequence = new Array(1,2,3,4,5,6,7,8,9);
			var block_temp= new Array();
			for (var i=0; i<=8; i++) {
				block_temp[i] = sudoku[Math.floor(block/3)*27+i%3+9*Math.floor(i/3)+3*(block%3)];
			}
			block_temp.sort();
			return block_temp.join() == right_sequence.join();
		}
		function is_solved_sudoku(sudoku) {
			for (var i=0; i<=8; i++) {
				if (!is_correct_block(i,sudoku) || !is_correct_row(i,sudoku) || !is_correct_col(i,sudoku)) {
					return false;
				}
			}
			return true;
		}
		function determine_possible_values(cell,sudoku) {
			var possible = new Array();
			for (var i=1; i<=9; i++) {
				if (is_possible_number(cell,i,sudoku)) {
					possible.unshift(i);
				}
			}
			return possible;
		}
		function determine_random_possible_value(possible,cell) {
			var random_picked = Math.floor(Math.random() * possible[cell].length);
			return possible[cell][random_picked];
		}
		function scan_sudoku_for_unique(sudoku) {
			var possible = new Array();
			for (var i=0; i<=80; i++) {
				if (sudoku[i] == 0) {
					possible[i] = new Array();
					possible[i] = determine_possible_values(i,sudoku);
					if (possible[i].length==0) {
						return false;
					}
				}
			}
			return possible;
		}
		function remove_attempt(attempt_array,number) {
			var new_array = new Array();
			for (var i=0; i<attempt_array.length; i++) {
				if (attempt_array[i] != number) {
					new_array.unshift(attempt_array[i]);
				}
			}
			return new_array;
		}
		function next_random(possible) {
			var mai = 9;
			var min_choices = 0;
			for (var i=0; i<=80; i++) {
				if (possible[i]!=undefined) {
					if ((possible[i].length<=mai) && (possible[i].length>0)) {
						mai = possible[i].length;
						min_choices = i;
					}
				}
			}
			return min_choices;
		}
		function show_sudoku(sudoku,i) {
			var sudokutext:TextField = new TextField();
			var format:TextFormat = new TextFormat();
			var solved = "\n\nSolved in "+i+" steps";
			format.font = "Lucida Console";
			sudokutext.width = 250;
			sudokutext.height = 250;
			sudokutext.defaultTextFormat = format;
			sudokutext.x = 25;
			sudokutext.y = 25;
			addChild(sudokutext);
			for (var i=0; i<=8; i++) {
				for (var j=0; j<=8; j++) {
					sudokutext.appendText(" ");
					sudokutext.appendText(sudoku[i*9+j]);
					sudokutext.appendText(" ");
					if (j!=8) {
						sudokutext.appendText("|");
					}
				}
				if (i!=8) {
					sudokutext.appendText("\n---+---+---+---+---+---+---+---+---\n");
				}
			}
			sudokutext.appendText(solved);
		}
		function solve(sudoku) {
			var saved = new Array();
			var saved_sud = new Array();
			var i=0;
			var next_move;
			var what_to_try;
			var attempt;
			while (!is_solved_sudoku(sudoku)) {
				i+=1;
				next_move = scan_sudoku_for_unique(sudoku);
				if (next_move == false) {
					next_move = saved.pop();
					sudoku = saved_sud.pop();
				}
				what_to_try = next_random(next_move);
				attempt = determine_random_possible_value(next_move,what_to_try);
				if (next_move[what_to_try].length>1) {
					next_move[what_to_try] = remove_attempt(next_move[what_to_try],attempt);
					saved.push(next_move.slice());
					saved_sud.push(sudoku.slice());
				}
				sudoku[what_to_try] = attempt;
			}
			show_sudoku(sudoku,i);
		}
	}
}