diff --git a/Semester 3/Assignments/templatesMatricesSample/src/main/java/edu/slcc/asdv/beans/MatrixBeanA.java b/Semester 3/Assignments/templatesMatricesSample/src/main/java/edu/slcc/asdv/beans/MatrixBeanA.java
index a53fcdf..cf56420 100644
--- a/Semester 3/Assignments/templatesMatricesSample/src/main/java/edu/slcc/asdv/beans/MatrixBeanA.java	
+++ b/Semester 3/Assignments/templatesMatricesSample/src/main/java/edu/slcc/asdv/beans/MatrixBeanA.java	
@@ -16,16 +16,15 @@ import java.util.ArrayList;
  */
 @Named(value = "matrixBeanA")
 @ViewScoped
-public class MatrixBeanA implements Serializable
-{
+public class MatrixBeanA implements Serializable {
+
     private int columns = 2;
     private int rows = 2;
     ArrayList<ArrayList<String>> matrix = new ArrayList<ArrayList<String>>();
 
-    public MatrixBeanA()
-    {
+    public MatrixBeanA() {
         matrix = new ArrayList<ArrayList<String>>();
-       BigInteger counter = BigInteger.ZERO;
+        BigInteger counter = BigInteger.ZERO;
         for (int i = 0; i < columns; ++i) {
             ArrayList<String> row = new ArrayList<>();
             for (int j = 0; j < rows; ++j) {
@@ -37,59 +36,58 @@ public class MatrixBeanA implements Serializable
         }
     }
 
-    public int getColumns()
-    {
+    public int getColumns() {
         return columns;
     }
 
-    public void setColumns(int columns)
-    {
+    public void setColumns(int columns) {
         this.columns = columns;
     }
 
-    public int getRows()
-    {
+    public int getRows() {
         return rows;
     }
 
-    public void setRows(int rows)
-    {
+    public void setRows(int rows) {
         this.rows = rows;
     }
 
-    public void listenForKeyUp(int i, int j, String input)
-    {
+    public void listenForKeyUp(int i, int j, String input) {
         System.out.println("i=" + i);
         System.out.println("j=" + j);
         System.out.println("input=" + input);
         matrix.get(i).set(j, input);
-        
+
     }
 
-    public ArrayList<ArrayList<String>> getMatrix()
-    {
+    public ArrayList<ArrayList<String>> getMatrix() {
         return matrix;
     }
-        public void changeRowsColumns() {
-            System.out.println("Columns:" + columns);
-            System.out.println("Rows:" + rows);
-            ArrayList<ArrayList<String>> resizedMatrix = new ArrayList<>();
-            for (int i = 0; i < rows; ++i) {
+
+    public void changeRowsColumns() {
+        System.out.println("Columns:" + columns);
+        System.out.println("Rows:" + rows);
+        ArrayList<ArrayList<String>> resizedMatrix = new ArrayList<>();
+
+        // Create a new resized matrix with the updated number of rows and columns
+        for (int i = 0; i < rows; ++i) {
             ArrayList<String> row = new ArrayList<>();
             for (int j = 0; j < columns; ++j) {
                 row.add("1");
             }
             resizedMatrix.add(row);
         }
-            // add the data from the old matrix to the new one
-            for (int i = 0; i < columns; ++i) {
-                for (int j = 0; j < rows; ++j) {
-                    if (i < matrix.size() && j < matrix.get(i).size()) {
-                        resizedMatrix.get(i).set(j, matrix.get(i).get(j));
-                    }
+
+        // Copy data from the old matrix to the new resized matrix
+        for (int i = 0; i < rows; ++i) {
+            for (int j = 0; j < columns; ++j) {
+                if (i < matrix.size() && j < matrix.get(i).size()) {
+                    resizedMatrix.get(i).set(j, matrix.get(i).get(j));
                 }
             }
-            // overwrite the old matrix
-            matrix = resizedMatrix;
+        }
+
+        // Overwrite the old matrix with the resized matrix
+        matrix = resizedMatrix;
     }
 }
diff --git a/Semester 3/Assignments/templatesMatricesSample/src/main/java/edu/slcc/asdv/beans/MatrixOperations.java b/Semester 3/Assignments/templatesMatricesSample/src/main/java/edu/slcc/asdv/beans/MatrixOperations.java
index 3de68b4..2ecc130 100644
--- a/Semester 3/Assignments/templatesMatricesSample/src/main/java/edu/slcc/asdv/beans/MatrixOperations.java	
+++ b/Semester 3/Assignments/templatesMatricesSample/src/main/java/edu/slcc/asdv/beans/MatrixOperations.java	
@@ -13,12 +13,11 @@ import java.util.ArrayList;
 
 /**
  *
- *  @author A. V. Markou
+ * @author A. V. Markou
  */
 @Named(value = "matrixOperations")
 @ViewScoped
-public class MatrixOperations implements Serializable
-{
+public class MatrixOperations implements Serializable {
 
     @Inject
     MatrixBeanA matrixA;
@@ -27,81 +26,91 @@ public class MatrixOperations implements Serializable
 
     @Inject
     MatrixBeanC matrixC;
-    
+
     edu.slcc.asdv.bl.Matrices matrixManipulator = new edu.slcc.asdv.bl.Matrices();
 
     public String add() {
-        
-        ArrayList<ArrayList<String>>  a =  matrixA.getMatrix();
-        ArrayList<ArrayList<String>>  b =  matrixB.getMatrix();
-        ArrayList<ArrayList<String>>  c =  new ArrayList<ArrayList<String>>();
-        
-        for ( int i=0; i < a.size(); ++i)
-        {
+
+        ArrayList<ArrayList<String>> a = matrixA.getMatrix();
+        ArrayList<ArrayList<String>> b = matrixB.getMatrix();
+        ArrayList<ArrayList<String>> c = new ArrayList<ArrayList<String>>();
+
+        for (int i = 0; i < a.size(); ++i) {
             ArrayList<String> row = new ArrayList<>();
-            for ( int j=0; j < a.size(); ++j)
-            {
-            Integer result =   Integer.parseInt ( a.get(i).get(j))
-                                    +
-                        Integer.parseInt ( b.get(i).get(j));
-             
-              row.add( result.toString() );
-             }
-          c.add(row);
-           System.out.println(row);
+            for (int j = 0; j < a.size(); ++j) {
+                Integer result = Integer.parseInt(a.get(i).get(j))
+                        + Integer.parseInt(b.get(i).get(j));
+
+                row.add(result.toString());
+            }
+            c.add(row);
+            System.out.println(row);
         }
-       matrixC.setMatrix( c );
-                return "";
+        matrixC.setMatrix(c);
+        return "";
     }
 
     public String multiply() {
-        ArrayList<ArrayList<BigInteger>>  a =  convertToBigInteger(matrixA.getMatrix());
-        ArrayList<ArrayList<BigInteger>>  b =  convertToBigInteger(matrixA.getMatrix());
-        ArrayList<ArrayList<String>>  c =  new ArrayList<ArrayList<String>>();
-        c = convertToString(matrixManipulator.multiplyParallel(a, b));
-        printArray(c);
-       matrixC.setMatrix( c );
-        return "";}
-        
-        public String subtract() {
-        
-        ArrayList<ArrayList<String>>  a =  matrixA.getMatrix();
-        ArrayList<ArrayList<String>>  b =  matrixB.getMatrix();
-        ArrayList<ArrayList<String>>  c =  new ArrayList<ArrayList<String>>();
-        
-        for ( int i=0; i < a.size(); ++i)
-        {
-            ArrayList<String> row = new ArrayList<>();
-            for ( int j=0; j < a.size(); ++j)
-            {
-            Integer result =   Integer.parseInt ( a.get(i).get(j))
-                                    -
-                        Integer.parseInt ( b.get(i).get(j));
-             
-              row.add( result.toString() );
-             }
-          c.add(row);
-           System.out.println(row);
+        ArrayList<ArrayList<BigInteger>> a = convertToBigInteger(matrixA.getMatrix());
+        ArrayList<ArrayList<BigInteger>> b = convertToBigInteger(matrixA.getMatrix());
+        ArrayList<ArrayList<String>> c = new ArrayList<ArrayList<String>>();
+
+        for (int i = 0; i < a.size(); i++) {
+            ArrayList<String> rowResult = new ArrayList<>();
+            for (int j = 0; j < b.get(i).size(); j++) {
+                BigInteger sum = BigInteger.ZERO;
+                for (int k = 0; k < a.get(0).size(); k++) {
+                    sum = sum.add(a.get(i).get(k).multiply(b.get(k).get(j)));
+                }
+                rowResult.add(sum.toString());
+            }
+            c.add(rowResult);
         }
-       matrixC.setMatrix( c );
-                return "";
+
+        printArray(c);
+        matrixC.setMatrix(c);
+        return "";
     }
 
- 
-    public MatrixBeanC getMatrixC(){return this.matrixC;}
+    public String subtract() {
 
-    public MatrixBeanA getMatrixA(){return matrixA;}
+        ArrayList<ArrayList<String>> a = matrixA.getMatrix();
+        ArrayList<ArrayList<String>> b = matrixB.getMatrix();
+        ArrayList<ArrayList<String>> c = new ArrayList<ArrayList<String>>();
+
+        for (int i = 0; i < a.size(); ++i) {
+            ArrayList<String> row = new ArrayList<>();
+            for (int j = 0; j < a.size(); ++j) {
+                Integer result = Integer.parseInt(a.get(i).get(j))
+                        - Integer.parseInt(b.get(i).get(j));
+
+                row.add(result.toString());
+            }
+            c.add(row);
+            System.out.println(row);
+        }
+        matrixC.setMatrix(c);
+        return "";
+    }
+
+    public MatrixBeanC getMatrixC() {
+        return this.matrixC;
+    }
+
+    public MatrixBeanA getMatrixA() {
+        return matrixA;
+    }
+
+    public MatrixBeanB getMatrixB() {
+        return matrixB;
+    }
 
-    public MatrixBeanB getMatrixB(){return matrixB;}
-    
-    /*
-    
     public ArrayList<ArrayList<BigInteger>> convertToBigInteger(ArrayList<ArrayList<String>> matrix) {
         ArrayList<ArrayList<BigInteger>> bigInt2DArray = new ArrayList<>();
 
         for (int i = 0; i < matrix.size(); i++) {
             ArrayList<BigInteger> columnArray = new ArrayList<BigInteger>();
-            for (int j = 0; j <  matrix.get(i).size(); j++) {
+            for (int j = 0; j < matrix.get(i).size(); j++) {
                 String cellValue = matrix.get(i).get(j);
                 columnArray.add(new BigInteger(cellValue));
             }
@@ -110,7 +119,7 @@ public class MatrixOperations implements Serializable
 
         return bigInt2DArray;
     }
-    
+
     public ArrayList<ArrayList<String>> convertToString(ArrayList<ArrayList<BigInteger>> matrix) {
         int numRows = matrix.size();
         int numCols = matrix.get(0).size();
@@ -125,7 +134,7 @@ public class MatrixOperations implements Serializable
         }
         return string2DArray;
     }
-*/
+
     /**
      *
      * @param matrix
@@ -143,7 +152,7 @@ public class MatrixOperations implements Serializable
         System.out.println(output);
         return output;
     }
-    
+
     public String printSingleArray(ArrayList<String> matrix) {
         String output = "\t{";
         for (int i = 0; i < matrix.size(); ++i) {
@@ -155,6 +164,5 @@ public class MatrixOperations implements Serializable
         output += "}";
         return output;
     }
-    
-    
+
 }
diff --git a/Semester 3/Assignments/templatesMatricesSample/src/main/java/edu/slcc/asdv/beans/MenuBar.java b/Semester 3/Assignments/templatesMatricesSample/src/main/java/edu/slcc/asdv/beans/MenuBar.java
index 8d98aee..0cb8fcb 100644
--- a/Semester 3/Assignments/templatesMatricesSample/src/main/java/edu/slcc/asdv/beans/MenuBar.java	
+++ b/Semester 3/Assignments/templatesMatricesSample/src/main/java/edu/slcc/asdv/beans/MenuBar.java	
@@ -75,7 +75,24 @@ public class MenuBar implements Serializable
         PrimeFaces.current().ajax().update(idsC);
     }
 
-   
+   public boolean areMatricesTheSameSize() {
+       int matrixAColumns = matrixOperations.getMatrixA().getColumns();
+       int matrixBColumns = matrixOperations.getMatrixB().getColumns();
+       int matrixCColumns = matrixOperations.getMatrixC().getColumns();
+       
+       int matrixARows = matrixOperations.getMatrixA().getRows();
+       int matrixBRows = matrixOperations.getMatrixB().getRows();
+       int matrixCRows = matrixOperations.getMatrixC().getRows();
+       
+       boolean matrixAEqual = (matrixAColumns == matrixARows);
+       boolean matrixBEqual = (matrixBColumns == matrixBRows);
+       boolean matrixCEqual = (matrixCColumns == matrixCRows);
+       
+       if (matrixAEqual && matrixBEqual && matrixCEqual) {
+           return true;
+       }
+       return false;
+   }
 
 
 
diff --git a/Semester 3/Assignments/templatesMatricesSample/src/main/webapp/matrices/menuMatrices.xhtml b/Semester 3/Assignments/templatesMatricesSample/src/main/webapp/matrices/menuMatrices.xhtml
index b5229db..3731177 100644
--- a/Semester 3/Assignments/templatesMatricesSample/src/main/webapp/matrices/menuMatrices.xhtml	
+++ b/Semester 3/Assignments/templatesMatricesSample/src/main/webapp/matrices/menuMatrices.xhtml	
@@ -17,7 +17,7 @@
                     <p:submenu id ="submenu_matrices" 
                                label="Matrix" icon="pi pi-table">
                         <p:menuitem title="This does addition" 
-                                    id ="menuitem_add" value="Add" disabled="false"
+                                    id ="menuitem_add" value="Add" disabled="#{!menuBar.areMatricesTheSameSize()}"
                                     action="#{menuBar.add()}"                            
                                     icon="pi pi-plus" update="id_message "/>
                         
@@ -28,7 +28,7 @@
                                     update="id_message"/>
                                                   
                         <p:menuitem title="Subtraction" id ="menuitem_subtract" value="Subtract"
-                                    action="#{menuBar.subtract}"  disabled="false"
+                                    action="#{menuBar.subtract}"  disabled="#{!menuBar.areMatricesTheSameSize()}"
                                     icon="pi pi-minus" update="id_message"/>
                     </p:submenu>
                 </p:menubar>