WebDec 16, 2024 · There are much more efficient ways of finding duplicates in list in python (yours is O(n^2)), and its probably just better using numpy library to do it: import numpy … WebWith most optimize way with respect to time and space complexity: Step-1: Start travelling the original array from last, Step-2: Once you find the given element. Step-3: Return the index = l - i -1; where l = total length of the array, i = index of the element in step-2. – ArunDhwaj IIITH. Sep 4, 2024 at 17:37.
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WebMar 23, 2012 · Then it goes to the next element 31, with index 1, and checks if element 31 is present in the input_list[2:] (i.e., from index 2 till end of list), Because 31 is present in input_list[2:], it will return 31. similarly it goes through all the elements in the list, and will return only the repeated/duplicate elements into a list. WebJan 3, 2016 · Use enumerate to keep track of the index and a set to keep track of element seen: l = [1, 1, 2, 3] inds = [] seen = set () for i, ele in enumerate (l): if ele not in seen: inds.append (i) seen.add (ele) If you want both: inds = [] seen = set () for i, ele in enumerate (l): if ele not in seen: inds.append ( (i,ele)) seen.add (ele)
WebJun 9, 2011 · You can use a list comprehension with enumerate: indices = [i for i, x in enumerate (my_list) if x == "whatever"] The iterator enumerate (my_list) yields pairs (index, item) for each item in the list. Using i, x as loop variable target unpacks these pairs into the index i and the list item x. WebJul 11, 2024 · Teams. Q&A for work. Connect and share knowledge within a single location that is structured and easy to search. Learn more about Teams
WebJul 26, 2024 · You can simply use function enumerate (lst) it returns elements index_number and value. for example lst [0] = 1 the case above index_number is 0 and value is 1 so you can just use enumerate function for returning index number using if condition (returns it when the value is 3) WebAug 26, 2024 · While working with Python list, sometimes, we require to check for duplicates and may also sometimes require to track their indices. This kind of …
WebNov 14, 2024 · Using generator expressions and comprehensions this is pretty straightforward. First let's get all values that appear more than once in a set. x = [1.2, 2.4, 3.1, 4.0, 5.6, 6.5, 1.2, 3.1, 8.1, 23.6, 29.3] multiples = set (a for a in set (x) if x.count (a) > 1) Now, to get the indexes, we can use enumerate and a list comprehension to only ...
WebApr 8, 2024 · Find indexes of consecutive items in lists. and return a 2d list with the indexes of the repeating values: new_list = [] i = 0 while i < len (x)-1: if x [i] == x [i+1]: new_list.append ( [x [i],x [i+1]] i += 1. x is not necessarily sorted but has at least one series of repeating values. For example x can also be: bricktown gospel fellowshipWebFeb 8, 2024 · To repeat the elements in a list in python, we insert the existing elements of a list to the same list. In this way, the elements in a list get repeated. For instance, If we … bricktown event centerWebAug 22, 2024 · How do I get the index of a duplicated string in a list? Traversing through the length of the list so that we can keep a track of each index and print the index. … bricktown events centerWebIndex: "Return the index in the list of the first item whose value is x." a simple solution would be: for i in range (len (top)): if top [i] == 3: print ('recommendation found at: ' + str (i)) Share Improve this answer Follow answered Apr 9, 2016 at 17:03 Maximilian Peters 29.6k 12 83 96 Add a comment Not the answer you're looking for? bricktowne signature villageWebFind an index of duplicate elements in list Python Example Simple example code. a = [1, 2, 3, 2, 1, 5, 6, 5, 5, 5] res = [idx for idx, item in enumerate (a) if item in a [:idx]] print (res) Output: Another example using collections You have … bricktown filmsWebOct 7, 2008 · @stefanct this likely does double the complexity, I believe the in operator on a list has linear runtime. @ApproachingDarknessFish stated it would iterate twice which answers your question, and is right in saying that doubling the linear complexity is … bricktown entertainment oklahoma cityWebApr 23, 2014 · Using a dictionary to count the items in a list (8 answers) Closed 6 months ago. I am new to Python. I am trying to find a simple way of getting a count of the number of elements repeated in a list e.g. MyList = ["a", "b", "a", "c", "c", "a", "c"] Output: a: 3 b: 1 c: 3 python python-2.7 Share Follow edited Feb 24, 2024 at 8:01 galoget 712 9 15 bricktown fort smith