您如何让用户输入一个数字并让该数字从列表中提取该数据单元格值？

Question

For the task that I have been assigned, you are told that when a person enters a number, that data cell value should be pulled from the list. How do I achieve this?

Answer 1

I assume you mean "data cell value" as "list item" at an index.

First there is input from the user, using the input function. If this is not a valid integer, the int function will raise an exception.

Then we must also check that the index given by the user is within the list size. The first element of a list is at index #0, and the last is # list-length - 1. For example, a 3-item list has elements at 0, 1, 2.

fruit = [ "Apples", "Oranges", "Rambutan", "Mango" ]

try:
    user_text = input("Enter fruit index: ")
    user_choice = int(user_text)
except:
    print("Bad Choice");
    user_choice = -1

if (user_choice >= 0 and user_choice < len(fruit)):
    print("Your Fruit is: " + fruit[user_choice])
else:
    print("Index out of range")

Eg:

# python3 ./fruit.py 
Enter fruit index: 2
Your Fruit is: Rambutan

# python3 ./fruit.py 
Enter fruit index: None of your business
Bad Choice
Choice out of range