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Day-9/readme.md

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+# Day 9: Creating Custom Lists
+
+## **Task**: Implement a Python program to create a list with user-specified elements and types.
+
+**Description**:  
+In this task, you will create a Python program that allows a user to build a custom list by specifying the number of elements and their types (strings or numbers). This program introduces concepts of user input handling, loops, and data type operations.
+
+### **Key Steps**:
+1. **User Input for List Length**:  
+   The user specifies how many elements the list will have. Use the `int` function to ensure the input is a number.
+
+2. **Loop for Adding Elements**:  
+   Use a `while` loop to add the specified number of elements to the list.
+
+3. **Type Selection**:  
+   - If the user selects "S", they will input a string.  
+   - If the user selects "N", they will input a number.  
+   - Handle invalid inputs gracefully.
+
+4. **Output the Final List**:  
+   Once all elements are added, print the complete list.
+
+---
+
+**Example**:
+```python
+# User specifies the length of the list
+limit = int(input("Enter length of list: "))
+
+# Initialize the counter and the list
+i = 0
+L = []
+
+# Loop to collect elements
+while i < limit:
+    ty = input("Enter data type (S for String / N for Number): ").upper()
+
+    if ty == "S":
+        element = input("Enter the string element: ")
+        L.append(element)
+        i += 1
+    elif ty == "N":
+        try:
+            element = int(input("Enter the number element: "))
+            L.append(element)
+            i += 1
+        except ValueError:
+            print("Invalid input! Please enter a number.")
+    else:
+        print("Invalid type! Please enter 'S' or 'N'.")
+
+# Output the final list
+print("Final List:", L)