diff --git a/contracts/StudentRegistry.sol b/contracts/StudentRegistry.sol
index 4f5bb554..c6220ce2 100644
--- a/contracts/StudentRegistry.sol
+++ b/contracts/StudentRegistry.sol
@@ -1,13 +1,105 @@
+// SPDX-License-Identifier: MIT
+// pragma solidity ^0.8.24;
+
+// contract StudentRegistry {
+//     //custom data type
+//     struct Student {
+//         address studentAddr;
+//         string name;
+//         uint256 studentId;
+//         uint8 age;
+//     }
+
+//     address public owner;
+
+//     constructor() {
+//         owner = msg.sender;
+//     }
+
+//     //dynamic array of students
+//     Student[] private students;
+
+//     mapping(address => Student) public studentsMapping;
+
+//     modifier onlyOwner () {
+//         require( owner == msg.sender, "You fraud!!!");
+//         _;
+//     }
+
+//     modifier isNotAddressZero () {
+//         require(msg.sender != address(0), "Invalid Address");
+//         _;
+//     }
+
+//     function addStudent(
+//         address _studentAddr,
+//         string memory _name,
+//         uint8 _age
+//     ) public onlyOwner isNotAddressZero {
+
+//         require( bytes(_name).length > 0, "Name cannot be blank");
+//         require( _age >= 18, "This student is under age");
+
+//         uint256 _studentId = students.length + 1;
+//         Student memory student = Student({
+//             studentAddr: _studentAddr,
+//             name: _name,
+//             age: _age,
+//             studentId: _studentId
+//         });
+
+//         students.push(student);
+//         // add student to studentsMapping
+//         studentsMapping[_studentAddr] = student;
+//     }
+
+//     function getStudent(uint8 _studentId) public isNotAddressZero view returns (Student memory) {
+//         return students[_studentId - 1];
+//     }
+
+
+
+//     function getStudentFromMapping(address _studentAddr)
+//         public
+//         isNotAddressZero
+//         view
+//         returns (Student memory)
+//     {
+//         return studentsMapping[_studentAddr];
+//     }
+
+
+
+//     function deleteStudent(address _studentAddr) public onlyOwner  isNotAddressZero{
+
+//         require(studentsMapping[_studentAddr].studentAddr != address(0), "Student does not exist");
+
+//         // delete studentsMapping[_studentAddr];
+
+//         Student memory student = Student({
+//             studentAddr: address(0),
+//             name: "",
+//             age: 0,
+//             studentId: 0
+//         });
+
+//         studentsMapping[_studentAddr] = student;
+
+//     }
+// }
+// `
+
+
+
 // SPDX-License-Identifier: MIT
 pragma solidity ^0.8.24;
 
 contract StudentRegistry {
-    //custom data type
     struct Student {
         address studentAddr;
         string name;
-        uint256 studentId;
         uint8 age;
+        uint256 studentId;
     }
 
     address public owner;
@@ -16,30 +108,37 @@ contract StudentRegistry {
         owner = msg.sender;
     }
 
-    //dynamic array of students
     Student[] private students;
 
-    mapping(address => Student) public studentsMapping;
+    mapping(address => Student) public studentMap;
 
-    modifier onlyOwner () {
-        require( owner == msg.sender, "You fraud!!!");
+    modifier onlyOwner() {
+        require(owner == msg.sender, "you're not authorized");
         _;
     }
 
-    modifier isNotAddressZero () {
+    modifier isNotAddressZero() {
         require(msg.sender != address(0), "Invalid Address");
         _;
     }
 
+    event StudentAdded(
+        address indexed studentAddr,
+        string name,
+        uint8 age,
+        uint256 studentId
+    );
+    event StudentDeleted(address indexed studentAddr);
+
+    /// @dev function to add student to the students array and mapping
+    /// @notice adds student
     function addStudent(
         address _studentAddr,
         string memory _name,
         uint8 _age
     ) public onlyOwner isNotAddressZero {
-
-        require( bytes(_name).length > 0, "Name cannot be blank");
-        require( _age >= 18, "This student is under age");
-
+        require(bytes(_name).length > 0, "input cannot be empty");
+        require(_age >= 18, "You are not up to age");
         uint256 _studentId = students.length + 1;
         Student memory student = Student({
             studentAddr: _studentAddr,
@@ -49,32 +148,60 @@ contract StudentRegistry {
         });
 
         students.push(student);
-        // add student to studentsMapping
-        studentsMapping[_studentAddr] = student;
+        studentMap[_studentAddr] = student;
+
+        emit StudentAdded(_studentAddr, _name, _age, _studentId);
     }
 
-    function getStudent(uint8 _studentId) public isNotAddressZero view returns (Student memory) {
+    /// @dev function to get student using studentId
+    /// @notice gets student ID
+    function getStudent(uint256 _studentId)
+        public
+        view
+        onlyOwner
+        isNotAddressZero
+        returns (Student memory)
+    {
         return students[_studentId - 1];
     }
 
-
-
-    function getStudentFromMapping(address _studentAddr)
+    /// @dev function to get student using studentAddr
+    /// @notice gets student Address
+    function getStudentAddr(address _ownerAddr)
         public
-        isNotAddressZero
         view
+        onlyOwner
+        isNotAddressZero
         returns (Student memory)
     {
-        return studentsMapping[_studentAddr];
+        return studentMap[_ownerAddr];
     }
 
+    function updateStudent(
+        address _studentAddr,
+        string memory _name,
+        uint8 _age,
+        uint256 _studentId
+    ) public onlyOwner isNotAddressZero {
+        Student storage studentToUpdate = studentMap[_studentAddr];
+        studentToUpdate.name = _name;
+        studentToUpdate.age = _age;
+        studentToUpdate.studentId = _studentId;
+    }
 
+    /// @dev function to delete using address
+    /// @notice resets it back to the initial state
+    function deleteStudent(address _studentAddr)
+        public
+        onlyOwner
+        isNotAddressZero
+    {
+        require(
+            studentMap[_studentAddr].studentAddr != address(0),
+            "student not available"
+        );
 
-    function deleteStudent(address _studentAddr) public onlyOwner  isNotAddressZero{
-
-        require(studentsMapping[_studentAddr].studentAddr != address(0), "Student does not exist");
-
-        // delete studentsMapping[_studentAddr];
+        // delete studentMap[_studentAddr];
 
         Student memory student = Student({
             studentAddr: address(0),
@@ -83,7 +210,22 @@ contract StudentRegistry {
             studentId: 0
         });
 
-        studentsMapping[_studentAddr] = student;
+        studentMap[_studentAddr] = student;
+
+        emit StudentDeleted(_studentAddr);
+    }
+
+    /// @dev function to delete using Uint
+    /// @notice resets it back to the initial state
+    function deleteStudentUint(uint256 _student)
+        public
+        onlyOwner
+        isNotAddressZero
+    {
+        require(_student > 0, "student not available or does not exist");
+
+        delete students[_student - 1];
 
+        emit StudentDeleted(students[_student - 1].studentAddr);
     }
-}
+}
\ No newline at end of file