Given a string containing characters ‘a’ and ‘b’ only. Convert the given string into a string in which there is no ‘ab’ substring. To make string ‘ab’ free we can perform an operation in which we select a ‘ab’ substring and replace it by ‘bba’.
Find the total number of operations required to convert the given string.
Input : s = 'abbaa' Output : 2 Explanation: Here, ['ab'baa] is replaced s = [bbabaa] [bb'ab'aa] is replaced s = [bbbbaaa] which is ab free. Hence, 2 operations required. Input : s = 'aab' Output : 3 Explanation: Here, [a'ab'] is replaced s = [abba] ['ab'ba] is replaced s = [bbaba] [bb'ab'a] is replaced s = [bbbbaa] which is ab free. Hence, 3 operations required.
The final state will be some character ‘a’ after ‘b’: “bbb…baaa…a”
It’s obvious to prove all ‘b’s are distinctive to each other(i.e. Each ‘b’ in the initial state, will add some number of ‘b’s to the final state disjoint from other ‘b’s). For a character ‘b’ from the initial state it will double after seeing a character ‘a’. For each i-th character ‘b’, consider ti the number of a before it. So the final number of ‘b’s can be defined as sumation of 2^ti.
Below is the implementation of above approach.
2 3 11
- Deletions of "01" or "10" in binary string to make it free from "01" or "10"
- Minimum cost to make a string free of a subsequence
- Operations required to make the string empty
- Minimal operations to make a number magical
- Minimum operations to make frequency of all characters equal K
- Minimum move to end operations to make all strings equal
- Minimum number of given operations required to make two strings equal
- Minimum operations required to make the string satisfy the given condition
- Binary array after M range toggle operations
- Minimum given operations required to convert a given binary string to all 1's
- Minimum operations required to convert a binary string to all 0s or all 1s
- Minimum number of operations required to sum to binary string S
- Count the number of carry operations required to add two numbers
- Minimum number of operations on a binary string such that it gives 10^A as remainder when divided by 10^B
- Count columns to be deleted to make each row sorted
If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to firstname.lastname@example.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.
Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.