correction de la methode getNeighbour qui donnait un mauvais nombre de voisin...

correction de la methode getNeighbour qui donnait un mauvais nombre de voisin (9) et correction de la méthode calculateNextState

Grid.java

@@ -107,7 +107,7 @@ public class Grid implements Iterable<Cell> {
     private boolean calculateNextState(int rowIndex, int columnIndex, Cell cell) {
         int aliveNeighbours = countAliveNeighbours(rowIndex, columnIndex);
         if (cell.isAlive()) {
-            return aliveNeighbours > 1 && aliveNeighbours < 4;
+            return aliveNeighbours >= 2 && aliveNeighbours <= 3;
         }
         return aliveNeighbours == 3;
     }
@@ -127,7 +127,7 @@ public class Grid implements Iterable<Cell> {
         List<Cell> cells = new ArrayList<>();
         for (int i =  rowIndex - 1; i <= rowIndex + 1; i++) {
             for (int j = columnIndex - 1; j <= columnIndex + 1; j++) {
-                if (i != rowIndex && j != columnIndex || i > 0 && j > 0 && i < getNumberOfRows() && j < getNumberOfColumns())
+                if ((!(i == rowIndex && j == columnIndex)) && i > 0 && j > 0 && i < getNumberOfRows() && j < getNumberOfColumns())
                     cells.add(getCell(i, j));
             }
         }