Compressed String

Lets convert all '$ab$' to '$bb$' as they can be minimized to '$b$'. Then as a result we will get one of the three types of strings after applying operations.

• If we get '$aaa...a$' then the minimized string will be '$a$'.
• If we get '$bbb...b$' then the minimized string will be '$b$'.
• If we get '$bbb...a$' then the minimized string will be '$ba$'.