CF2182A New Year String

We will call a string consisting of characters 0, 2, 5, and/or 6 a New Year string if at least one of the two conditions is met: - it contains the string 2026 as a continuous substring; - it does not contain the string 2025 as a continuous substring. For example, the strings 20252026, 21026, 20262026, 000 are New Year strings. The strings 2025, 20256, 20252025, 000202500020226 are not New Year strings. You are given a string $ s $ . You can perform the following operation any number of times (possibly zero): - choose a character in the string $ s $ and replace it with 0, 2, 5, or 6 (you can choose any one of these four characters). Calculate the minimum number of operations needed to make the string $ s $ a New Year string.

The first line contains one integer $ t $ ( $ 1 \le t \le 10^4 $ ) — the number of test cases. Each test case consists of two lines: - the first line contains one integer $ n $ ( $ 4 \le n \le 20 $ ) — the number of characters in $ s $ ; - the second line contains $ s $ — a sequence of $ n $ characters 0, 2, 5, and/or 6.

For each test case, output one integer — the minimum number of operations needed to make the string $ s $ a New Year string.

In the second example from the statement, you can replace the $ 2 $ -nd character of the string with 2. Then the string will become 2225. In the fifth example from the statement, you can replace the $ 4 $ -th character with 6. Then the string will become 20262025. In the sixth example from the statement, you can replace the $ 8 $ -th character with 6. Then the string will become 202520266.