diff --git a/CS_Source Code.py b/CS_Source Code.py
new file mode 100644
index 0000000..d2dd326
--- /dev/null
+++ b/CS_Source Code.py	
@@ -0,0 +1,197 @@
+"""to maintain student details 
+roll number
+name 
+percentage
+""" 
+""" 
+modules imported 
+""" 
+import pickle 
+import os
+import time
+""" 
+class used 
+"""
+class student(object):
+    def __int__(s): 
+        s.roll=0 
+        s.name="" 
+        s.per=0 
+    def add_rec(s): 
+        s.roll=int(input("Enter roll number: ")) 
+        s.name=input("Enter name: ") 
+        s.name=s.name.upper() 
+        s.per=float(input("Enter percentage: ")) 
+    def disp_rec(s): 
+        print("roll number: ",s.roll) 
+        print("name: ",s.name) 
+        print("percentage: ",s.per) 
+    def display_rec(s): 
+        print("%-10s"%s.roll,"%-20s"%s.name,"%-10s"%s.per) 
+        #print("in display_rec") 
+    def modify_rec(s): 
+        s.roll=int(input("Enter new roll number: ")) 
+        s.name=input("Enter new name: ") 
+        s.name=s.name.upper()
+        s.per=float(input("Enter new percentage: "))
+def write_record(): 
+    try: 
+        rec=student() 
+        file=open("stud.dat","ab") 
+        rec.add_rec() 
+        pickle.dump(rec,file) 
+        file.close() 
+        print("Record added in file!") 
+        input("Press any key to continue....") 
+    except: 
+        pass 
+def display_all():  
+    print(40*"=") 
+    print("\n\t    Student Records\n") 
+    print(40*"=") 
+    try: 
+        file=open("stud.dat","rb") 
+        while True: 
+            rec=pickle.load(file) 
+            rec.display_rec() 
+    except EOFError: 
+        file.close() 
+        print(40*"=") 
+        input("Press any key to continue....") 
+    except IOError: 
+        print("File could not be opened!!") 
+def search_roll(): 
+    try: 
+        z=0 
+        print(40*"=") 
+        print("Record searching by roll number...") 
+        print(40*"=") 
+        n=int(input("Enter roll number to search: ")) 
+        file=open("stud.dat","rb") 
+        while True: 
+            rec=pickle.load(file) 
+            #print(rec.roll) 
+            if(rec.roll==n): 
+                z=1 
+                print("\nRecord found and details are:\n") 
+                rec.disp_rec() 
+                break 
+    except EOFError: 
+        file.close() 
+        if(z==0): 
+            print("Record is not present!!") 
+    except IOError: 
+        print("File could not be opened!!") 
+    input("Press any key to continue....") 
+def search_name(): 
+    try: 
+        z=0
+        print(40*"=") 
+        print("Record searching by name...") 
+        print(40*"=")
+        n=input("Enter name to search: ") 
+        file=open("stud.dat","rb") 
+        while True: 
+            rec=pickle.load(file) 
+            #print(rec.roll) 
+            if(rec.name==n.upper()): 
+                z=1
+                print("\nRecord found and details are:\n")
+                rec.disp_rec() 
+                break 
+    except EOFError:
+        file.close() 
+        if(z==0): 
+            print("Record is not present!!") 
+    except IOError: 
+        print("File could not be opened!!")
+    input("Press any key to continue....") 
+def modify_roll():  
+    z=0 
+    try: 
+        n=int(input("Enter roll number to modify: ")) 
+        file=open("stud.dat","rb") 
+        temp=open("temp.dat","wb") 
+        while True: 
+            rec=pickle.load(file) 
+            if(rec.roll==n): 
+                z=1 
+                print("\nRecord found and details are:\n") 
+                rec.disp_rec() 
+                print("\nEnter new data...") 
+                rec.modify_rec() 
+                pickle.dump(rec,temp) 
+                print("Record updated!") 
+            else: 
+                pickle.dump(rec,temp)
+    except EOFError: 
+        file.close() 
+        temp.close() 
+        if(z==0): 
+            print("Record not found!!") 
+    except IOError: 
+        print("File could not be opened!!") 
+    os.remove("stud.dat") 
+    os.rename("temp.dat","stud.dat") 
+    input("Press any key to continue....") 
+def delete_roll(): 
+    z=0 
+    try: 
+        n=int(input("Enter roll number to delete: ")) 
+        file=open("stud.dat","rb") 
+        temp=open("temp.dat","wb") 
+        while True: 
+            rec=pickle.load(file) 
+            if(rec.roll==n): 
+                z=1 
+                print("\nRecord to delete found and details are:\n") 
+                rec.disp_rec() 
+                #pickle.dump(rec,temp) 
+                print("Record updated!") 
+            else: 
+                pickle.dump(rec,temp) 
+    except EOFError: 
+        file.close() 
+        temp.close() 
+        if(z==0): 
+            print("Record not found!!") 
+    except IOError: 
+        print("File could not be opened!!") 
+    os.remove("stud.dat") 
+    os.rename("temp.dat","stud.dat") 
+    input("Press any key to continue....") 
+while True: 
+    os.system("cls")
+    print(40*"=") 
+    print("""              Main Menu 
+              --------- 
+        1. Add record 
+        2. Display all records 
+        3. Search by roll number 
+        4. Search by name 
+        5. Modify by roll number 
+        6. Delete by roll number 
+        7. Exit 
+    """) 
+    print(40*"=") 
+    ch=int(input("Enter your choice: ")) 
+    print(40*"=") 
+    if(ch==1): 
+        write_record() 
+    elif(ch==2): 
+        display_all() 
+    elif(ch==3): 
+        search_roll() 
+    elif(ch==4): 
+        search_name() 
+    elif(ch==5): 
+        modify_roll() 
+    elif(ch==6): 
+        delete_roll() 
+    elif(ch==7): 
+        print("\n\t      !!!End!!!\n")
+        time.sleep(2)
+        break
+    else: 
+        print("Invalid choice!!")
+        time.sleep(1)
diff --git a/stud.dat b/stud.dat
new file mode 100644
index 0000000..1fe08aa
Binary files /dev/null and b/stud.dat differ