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You are given a decimal number $S$ of length $N$.

You may delete some characters from $S$. The relative order of the remaining characters does not change. At least one character must remain.

The number formed by the remaining characters must be divisible by $6$ or by $7$. Find the minimum number of characters to delete. If this is impossible, print $-1$.

The resulting string may begin with $0$. For example, $\texttt{007}$ represents the decimal number $7$. The number $0$ is divisible by both $6$ and $7$.

The input is given in the following format:

$T$ $\mathrm{case}_1$ $\mathrm{case}_2$ $\vdots$ $\mathrm{case}_T$

Each case is given in the following format:

$N$ $S$

$T$ is the number of test cases. $S$ is a decimal number of length $N$.

For each test case, print the minimum number of characters to delete on one line. If it is impossible, print $-1$.

• $1 \leq T \leq 200\,000$.
• $1 \leq N \leq 200\,000$.
• The first character of $S$ is not $0$, and every character is a digit.
• The sum of $N$ over all test cases is at most $200\,000$.