Given a string and a number N, we need to mirror the characters from the N-th position up to the length of the string in alphabetical order. In mirror operation, we change ‘a’ to ‘z’, ‘b’ to ‘y’, and so on.
Examples:
Input : N = 3
paradox
Output : paizwlc
We mirror characters from position 3 to end.
Input : N = 6
pneumonia
Output : pneumlmrz
We have an existing solution for this problem please refer to Mirror characters of a string link. We can solve this problem in Python using Dictionary Data Structure. The mirror value of ‘a’ is ‘z’,’b’ is ‘y’, etc, so we create a dictionary data structure and one-to-one map reverse sequence of alphabets onto the original sequence of alphabets. Now traverse characters from length k in given string and change characters into their mirror value using a dictionary.
Implementation:
Python3
# function to mirror characters of a stringdef mirrorChars(input,k): # create dictionary original = 'abcdefghijklmnopqrstuvwxyz' reverse = 'zyxwvutsrqponmlkjihgfedcba' dictChars = dict(zip(original,reverse)) # separate out string after length k to change # characters in mirror prefix = input[0:k-1] suffix = input[k-1:] mirror = '' # change into mirror for i in range(0,len(suffix)): mirror = mirror + dictChars[suffix[i]] # concat prefix and mirrored part print (prefix+mirror) # Driver programif __name__ == "__main__": input = 'paradox' k = 3 mirrorChars(input,k) |
Output
paizwlc
Time complexity: O(n)
Auxiliary Space: O(n)
