diff --git a/FindAllNoDisappearedInArray.java b/FindAllNoDisappearedInArray.java
new file mode 100644
index 00000000..d2da45e3
--- /dev/null
+++ b/FindAllNoDisappearedInArray.java
@@ -0,0 +1,34 @@
+import java.util.List;
+import java.util.ArrayList;
+// Time Complexity : O(N)
+// Space Complexity : O(1)
+// Did this code successfully run on Leetcode : yes
+// Any problem you faced while coding this :
+
+
+// Your code here along with comments explaining your approach
+class Solution {
+    public List<Integer> findDisappearedNumbers(int[] nums) {
+        for(int i = 0; i < nums.length; i++)
+        {
+            int numIndex = Math.abs(nums[i]) - 1;
+            if(nums[numIndex] > 0)
+            {
+                nums[numIndex] *= -1;
+            }
+        }
+        List<Integer> result = new ArrayList<>();
+        for(int i = 0; i < nums.length; i++)
+        {
+            if(nums[i] < 0)
+            {
+                nums[i] *= -1;
+            }
+            else
+            {
+                result.add(i+1);
+            }
+        }
+        return result;
+    }
+}
diff --git a/GameOfLife.java b/GameOfLife.java
new file mode 100644
index 00000000..8fd97c10
--- /dev/null
+++ b/GameOfLife.java
@@ -0,0 +1,71 @@
+// Time Complexity : O(M*N)
+// Space Complexity : O(1)
+// Did this code successfully run on Leetcode : yes
+// Any problem you faced while coding this :
+
+
+// Your code here along with comments explaining your approach
+
+class Solution {
+    public void gameOfLife(int[][] board) {
+        // 0 - dead, 1 - live
+        // 1 -> < 2 live 1 -> 0
+        // 1 -> == 2 or == 3 live 1 -> 1
+        // 1 -> >3 live 1 -> 0
+        // 0 -> == 3 live 1 -> 1
+        // temporary pattern
+        //map 0 -> 1 -> 2
+        //map 1 -> 0 -> 3
+        for(int i = 0; i < board.length; i++)
+        {
+            for(int j = 0; j < board[0].length; j++)
+            {
+                int liveNeighbors = checkLive(i, j, board);
+                if(board[i][j] == 1 && (liveNeighbors < 2 || liveNeighbors > 3))
+                {
+                    board[i][j] = 3;
+                }
+                else if(board[i][j] == 0 && liveNeighbors == 3)
+                {
+                    board[i][j] = 2;
+                }
+            }
+        }
+
+        for(int i = 0; i < board.length; i++)
+        {
+            for(int j = 0; j < board[0].length; j++)
+            {
+                if(board[i][j] == 2)
+                {
+                    board[i][j] = 1;
+                }
+                else if(board[i][j] == 3)
+                {
+                    board[i][j] = 0;
+                }
+            }
+        }
+    }
+
+    private static int checkLive(int row, int col, int[][] board)
+    {
+        int[][] neighbors = new int[][]{{0,-1},{0,1},{-1,0},{-1,-1},{-1,1},{1,0},{1,-1},{1,1}};
+        int result = 0;
+
+        for(int[] neighbor : neighbors)
+        {
+            int nr = row + neighbor[0];
+            int nc = col + neighbor[1];
+            if(nr >= 0 && nc >= 0 && nr < board.length && nc < board[0].length)
+            {
+                if(board[nr][nc] == 1 || board[nr][nc] == 3)
+                {
+                    result++;
+                }
+            }
+        }
+
+        return result;
+    }
+}
\ No newline at end of file