You are given a password and you need to generate the number of steps required to convert the given password to a strong password. A password is considered strong if (a) it has at least 6 characters and at most 20 characters; (b) it contains at least one lowercase letter and one uppercase letter, and at least one digit; (c) it does not contain three repeating characters in a row. In one step you can: (1) Insert one character to password, (2) delete one character from password, or (3) replace one character of password with another character.
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Question: password = FZr7ToW3JcxtY2qvc72x6AgNryboz

Answer: 9


Question: password = cfBFAHlsvC86mSySLC2tvmsc49AfsTynD3Fdg

Answer: 17


Question: password = Nk

Answer:
4