在 Python 中用户输入给定的索引处打印值

Question

I am very new to programming in Python, this is something that seems so simple, but I just don't seem to be able to get it right.

I have a list of values.
I want to prompt the user for input.
Then print out the value that's at the corresponding index number in the list.

myList [0, 1, 20, 30, 40]    
choice = input()    
print (......)

If the user inputs 2, I want to print the the value that is at the index 2 (20). I am unsure of what to put after print.

Answer 1

You can do this by accessing the list using the given input by the user.

The input given by the user I assume would be a String, so we need to use int() to change it to an integer.

print myList[int(choice)]

Additionally, you may want to first check the validity of the input supplied; it cannot be less than 0, or more than the length of the list - 1;

choice = int(choice)
if (choice < 0 || choice >= len(myList))
   print('Not Valid')
else
   print myList[int(choice)]