Answer:
```python
sales_data = [10, 'Gil', 8, 'Aya', 17, 'Taj', 5, 'Dan', 18, 'Del', 7, 'Ava', 14, 'Ada']
sales_person_num = int(input())
# Ensure the input is within the range of indices
if sales_person_num >= 0 and sales_person_num * 2 + 1 < len(sales_data):
# Index of the number of sales
sales_index = sales_person_num * 2
# Index of the sales person's name
name_index = sales_index + 1
# Retrieve the number of sales and name from the sales_data list
num_sales = sales_data[sales_index]
name = sales_data[name_index]
# Print the result
print(sales_data[name_index], 'made', sales_data[sales_index], 'today.')
else:
print("Invalid input.")
```
This code snippet takes an integer input `sales_person_num` and retrieves the corresponding sales data from the `sales_data` list. It then prints the name of the salesperson and the number of sales made by that person. If the input is invalid (outside the range of indices), it prints "Invalid input."
