Given a string str consisting of characters and numbers and an integer k, the task is to decrypt the string and the return the kth character in the decrypted string.
In order to decrypt the string, traverse the string character by character and if the current character is an alphabet then append it to the resultant string else if it is a numeric digit then parse the number and repeat the resultant string this parsed number of times and continue with the original string. For example, str = “ab2c3” will be decrypted as “ababcababcababc”.
Input: str = “ab2c3”, k = 5
Decrypted string will be “ababcababcababc” and ‘c’ is the fifth character.
Input: str = “x2y3”, k = 3
- Initialize starting index i = 0 and total_len = 0.
- Loop while i is less then the length of the input string and check if current character is an alphabet or not. If yes then increment total_len by 1 and check if total length is less then or equal to k if yes then return the string else increment i.
- Initialize n = 0 again loop while i is less then length of input string and i is not an alphabet and parse the number and increment i and find the next_total_len = total_len * n.
- If k < total_len then get the position of the character by initializing pos = k % total_len.
- If position is not found then update position = total_len and finally return the character at kth position. If not found then return -1.
Below is the implementation of the above approach:
- Find a string such that every character is lexicographically greater than its immediate next character
- Find the character in first string that is present at minimum index in second string
- Queries to find the last non-repeating character in the sub-string of a given string
- Queries to find the first non-repeating character in the sub-string of a string
- Program to count occurrence of a given character in a string
- Find k-th character of decrypted string | Set - 2
- Find last index of a character in a string
- Find the first repeated character in a string
- Find the last non repeating character in string
- Find one extra character in a string
- Find k'th character of decrypted string | Set 1
- Given a string, find its first non-repeating character
- Find repeated character present first in a string
- Program to find second most frequent character
- Find the character made by adding all the characters of the given string
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