Examples:
Input: str = pythonengineering, k = 3 Output: r First non-repeating character is f, second is o and third is r. Input: str = pythonengineering, k = 2 Output: o Input: str = pythonengineering, k = 4 Output: Less than k non-repeating characters in input.
This problem has an existing solution, please refer to the List Comp Representation and < code class = "comments"> # OrderedDict returns dictionary data Output: This article courtesy of Shashank Mishra (Gullu) . If you are as Python.Engineering and would like to contribute, you can also write an article using contribute.python.engineering or by posting an article contribute @ python.engineering. See my article appearing on the Python.Engineering homepage and help other geeks. Please post comments if you find anything wrong or if you’d like to share more information on the topic discussed above. # Function for finding the kth non-repeating character
# in a line from collections import OrderedDict def kthRepeating ( input , k): # structure with input characters # string as keys in the same order as they are # were inserted and 0 as default dict = OrderedDict.fromkeys ( input , 0 ) # now go to the input line to calculate # frequency of each character for ch in input : dict [ch] + = 1 # now retrieve a list of all keys whose value # 1 from the order dictionary nonRepeatDict = [key for (key, value ) in dict . iteritems () if value = = 1 ] # now returns the (k-1) th character from the list above if len (nonRepeatDict) & lt; k: return ’Less than k non - repeating characters in input . ’ else : return nonRepeatDict [k - 1 ]
# Driver function if __ name__ = = "__ main __" : input = "pythonengineering" k = 3 print kthRepeating ( input , k) r
K-th non-repeating character in Python using list comprehension and OrderedDict Python functions: Questions
K-th non-repeating character in Python using list comprehension and OrderedDict repeat: Questions
