diff --git a/First Program b/First Program
index c501459..1179e7f 100644
--- a/First Program	
+++ b/First Program	
@@ -1,4 +1,37 @@
-a = int(input("enter first number: "))
-b = int(input("enter second number: "))
-sum = a + b.
-print("Sum:", sum)
+# define functions  
+def add(x, y):  
+   """This function adds two numbers"" 
+   return x + y 
+def subtract(x, y): 
+   """This function subtracts two numbers""" 
+   return x - y 
+def multiply(x, y): 
+   """This function multiplies two numbers""" 
+   return x * y 
+def divide(x, y): 
+   """This function divides two numbers"""  
+   return x / y  
+# take input from the user  
+print("Select operation.")  
+print("1.Add")  
+print("2.Subtract")  
+print("3.Multiply")  
+print("4.Divide")  
+  
+choice = input("Enter choice(1/2/3/4):")  
+  
+num1 = int(input("Enter first number: "))  
+num2 = int(input("Enter second number: "))  
+  
+if choice == '1':  
+   print(num1,"+",num2,"=", add(num1,num2))  
+  
+elif choice == '2':  
+   print(num1,"-",num2,"=", subtract(num1,num2))  
+  
+elif choice == '3':  
+   print(num1,"*",num2,"=", multiply(num1,num2))  
+elif choice == '4':  
+   print(num1,"/",num2,"=", divide(num1,num2))  
+else:  
+   print("Invalid input")