1. Question 1

Given a string s of lowercase English characters, the following operation can be performed any number of times:

Choose three consecutive characters s[i], s[i+1], and s[i+2] where (1 ≤ i ≤ |s| - 2, 1-based indexing) such that s[i] == s[i+1] and s[i+1] != s[i+2]. Replace s[i+2] with s[i].

Find the maximum number of operations that can be applied to s.

Example

s = "accept":

The following operations are performed (bold indicates changed character):

1. Start at i = 2, "cce": The new string s′ = "acccpt"
2. Start at i = 3, s′ = "acccct"
3. Start at i = 4, s′ = "accccc"

No other selections are available. The operation can be applied a maximum of 3 times.

Function Description

Complete the function getMaximumOperations in the editor with the following parameters:

• string s: the string to transform

Returns

• long_int: the maximum number of times the operation can be applied

Constraints

• 3 ≤ length of s ≤ 2 × 10⁵
• The string s only contains lowercase English letters

2. Question 2

Implement a session-based authentication system that manages user sessions with unique tokens and configurable time-to-live (TTL) values. Each token has an expiration time calculated by adding the TTL (in seconds) to the creation time. Tokens can be renewed before expiration to extend their validity. The system must support these three operations:

1. generate <token_id> <current_time>:
   At the current time, creates a new token with the specified ID.
2. renew <token_id> <current_time>:
   At the current time, extends an existing, unexpired token’s expiration time. The request is ignored if the token has expired or does not exist.
3. count <current_time>:
   Returns the number of unexpired tokens at the current time.

Important Note: Token expiration is evaluated before processing any actions at the same timestamp. If a token’s expiration time exactly matches the current time, the token is considered expired and cannot be renewed or counted.

Example

Suppose time_to_live = 5, and
queries = ["generate aaa 1", "renew aaa 2", "count 6", "generate bbb 7", "renew aaa 8", "renew bbb 10", "count 15"].

The output of the system is [1, 0].
At t = 6, the only unexpired token is "aaa". At t = 15, all tokens have expired, so the count of unexpired tokens is 0.

Function Description

Complete the function getUnexpiredTokens in the editor with the following parameter(s):

• int time_to_live: the time to live for a token
• string queries[q]: the queries

Returns

• int[]: the results of the count queries, in the same order as they appear

Constraints

• 1 ≤ q ≤ 100000
• 1 ≤ |queries| ≤ 10⁵
• 1 ≤ time_to_live ≤ 10⁸
• 1 ≤ current_time ≤ 10⁸
• 1 ≤ length of token_id ≤ 10
• token_id consists only of lowercase letters and numbers
• All queries of type generate will contain unique values of token_id
• current_time is in non-decreasing order in the queries

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