Enumerate() in Python

A lot of times when dealing with iterators, we also get a need to keep a count of iterations. Python eases the programmers’ task by providing a built-in function enumerate() for this task.
Enumerate() method adds a counter to an iterable and returns it in a form of enumerate object. This enumerate object can then be used directly in for loops or be converted into a list of tuples using list() method.
Syntax:

enumerate(iterable, start=0)
Parameters:
Iterable: any object that supports iteration
Start: the index value from which the counter is 
to be started, by default it is 0 
# Python program to illustrate
# enumerate function
l1 = ["eat","sleep","repeat"]
s1 = "geek"

# creating enumerate objects
obj1 = enumerate(l1)
obj2 = enumerate(s1)

print "Return type:",type(obj1)
print list(enumerate(l1))

# changing start index to 2 from 0
print list(enumerate(s1,2))
Output:
Return type: 
[(0, 'eat'), (1, 'sleep'), (2, 'repeat')]
[(2, 'g'), (3, 'e'), (4, 'e'), (5, 'k')]

Using Enumerate object in loops

# Python program to illustrate
# enumerate function in loops
l1 = ["eat","sleep","repeat"]

# printing the tuples in object directly
for ele in enumerate(l1):
	print ele
print 
# changing index and printing separately
for count,ele in enumerate(l1,100):
	print count,ele

Output:
(0, 'eat')
(1, 'sleep')
(2, 'repeat')

100 eat
101 sleep
102 repeat

This article is contributed by Harshit Agrawal. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

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