Given a string s written in median form, change it back to the original string. Median letter in a string is the letter which is in the middle of the string. If the string’s length is even, the median letter is the left of the two middle letters. The given string is formed by writing down the median letter of the word, then deleting it and repeating the process until there are no letters left.
Input: eekgs Output: geeks Explanation: in the original string “geeks” can be written in median form by picking up e first then, again e, then k then g and at the end s. As these are the median when the median letter is picked and deleted. Input: abc Output: bac Explanation: median of bac is a, then median of bc is b, then median of c is c.
To find the answer we can iterate through the given encoded string from left to right and add each letter in the answer string, one letter to the begin, next letter to the end, next letter to begin and so on. If n is even than the first letter must be added to the begin and the second letter to the end. In the other case, the first letter to the end, second to the begin. We need to make it until we do not add all letters from the given string.
Note: For strings with even length, when we add first character to begin and second character to end then the remaining string will always be of even length. Same is true for strings with odd lengths.
Given below is the implementation of the above approach
Time complexity: O(n)
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