begin multidoku display code

app/src/main/java/sudoku/structure/Block.java

@@ -7,6 +7,9 @@ public class Block {
 
 	private final List<Cell> cells;
 
+	// faster access to the sudoku
+	private List<Sudoku> sudokus;
+
 	public Block(List<Cell> cells) {
 		this.cells = cells;
 	}
@@ -39,4 +42,12 @@ public class Block {
 		}
 		return false;
 	}
+
+	public List<Sudoku> getSudokus() {
+		return sudokus;
+	}
+
+	void setSudokus(List<Sudoku> sudokus) {
+		this.sudokus = sudokus;
+	}
 }

app/src/main/java/sudoku/structure/Coordinate.java

@@ -30,4 +30,12 @@ public class Coordinate {
         return this.y * size + this.x;
     }
 
+    public Coordinate add(Coordinate other) {
+        return new Coordinate(this.x + other.x, this.y + other.y);
+    }
+
+    public Coordinate sub(Coordinate other) {
+        return new Coordinate(this.x - other.x, this.y - other.y);
+    }
+
 }

app/src/main/java/sudoku/structure/Sudoku.java

@@ -15,6 +15,7 @@ public class Sudoku {
 	private final List<Cell> cells;
 	private final List<IConstraint> constraints;
 	private boolean isMutable;
+	private int blockWidth;
 
 	public Sudoku(List<Cell> cells, List<Block> blocks, List<IConstraint> constraints) {
 		this.cells = cells;
@@ -23,7 +24,7 @@ public class Sudoku {
 	}
 
 	public int[] toCoords(int index) {
-		return new int[]{index % getSize(), index / getSize()};
+		return new int[] { index % getSize(), index / getSize() };
 	}
 
 	public int toIndex(int x, int y) {
@@ -71,6 +72,10 @@ public class Sudoku {
 		}
 	}
 
+	public int getBlockWidth() {
+		return blockWidth;
+	}
+
 	/**
 	 * Try to place a cell at the given coordinate
 	 *
@@ -162,6 +167,8 @@ public class Sudoku {
 			throw new Exception("The given cell is not in this sudoku.");
 		}
 
+		// TODO: use this.cells.indexOf();
+
 		for (Cell cell : this.cells) {
 			if (cell == c) {
 				return new Coordinate(x, y);