Accessing the index in 'for' loops?

Question

How do I access the index itself for a list like the following? ints = [8, 23, 45, 12, 78]When I loop through it using a `for` loop, how do I access the loop index, from 1 to 5 in this case?

Answer 1

You can use the built-in enumerate function:

my_list = ['python', 'is', 'the', 'GOAT']

for i, word in enumerate(my_list):

print(i, word)

# 0 python

# 1 is

# 2 the

# 3 GOAT

This function yields the index and the item in the list to the two variables in the for loop. This also is only linear in complexity whereas the answer utilizing the index() function would be quadratic time.

Hope that helps :)

Answer 2

Hi, I'm happy to help you,

You can use the list method ".index()", that returns that index of the element inside the parentheses. (see the code below). If you already understand how for loops work, you can see I used "i" inside the parentheses.

NOTE: Python uses 0-based indexing. That means that printing the index of those five elements, using the code below, will display: 0, 1, 2, 3, 4

If you need your output to actually be "1,2,3,4,5" instead. What simple modification would you do to that code? Let me know if you have any questions.

ints = [8, 23, 45, 12, 78]

for i in ints:

print(ints.index(i))