https://www.geeksforgeeks.org/final-string-after-performing-given-operations/
https://www.geeksforgeeks.org/final-state-of-the-string-after-modification/
Given a string str containing only characters x and y, the task is to perform the following operations while possible:
Find an index such that s[i] = ‘x’ and s[i+1] = ‘y’ and delete both the characters s[i] and s[i+1], if no such index is found then find an index such that s[i] = ‘y’ and s[i+1] = ‘x’ and swap(s[i], s[i+1]).
Print the final string after performing the given operation.
Find an index such that s[i] = ‘x’ and s[i+1] = ‘y’ and delete both the characters s[i] and s[i+1], if no such index is found then find an index such that s[i] = ‘y’ and s[i+1] = ‘x’ and swap(s[i], s[i+1]).
Print the final string after performing the given operation.
Examples:
Input: str = “xyyxx”
Output: x
Step 1: yxx (xy got deleted)
Step 2: xyx (yx got swapped)
Step 3: x (xy got deleted)Input: str = “xxyyxyy”
Output: y
Approach: In the final string there will be either only x or only y because if we have both xand y in the string then there would be a point where we have either xy or yx as sub-string.
- If it’s xy, we delete it straight away.
- If it is yx, we reverse it to get xy and then delete it.
Since in each deletion step, one x and one y gets deleted, the final string would have min(x, y) number of x and y characters deleted.