A14759. Banknotes

In Berland, $n$ different types of banknotes are used. Banknotes of the $i$ -th type have denomination $10^{a_i}$ burles (burles are the currency used in Berland); the denomination of banknotes of the first type is exactly $1$ .

Let's denote $f(s)$ as the minimum number of banknotes required to represent exactly $s$ burles. For example, if the denominations of banknotes used in Berland are $1$ , $10$ and $100$ , then $f(59) = 14$ : $9$ banknotes with denomination of $1$ burle and $5$ banknotes with denomination of $10$ burles can be used to represent exactly $9 \cdot 1 + 5 \cdot 10 = 59$ burles, and there's no way to do it with fewer banknotes.

For a given integer $k$ , find the minimum positive number of burles $s$ that cannot be represented with $k$ or fewer banknotes (that is, $f(s) > k$ ).

The first line contains a single integer $t$ ( $1 \le t \le 10^4$ ) — number of test cases.

The first line of each test case contains two integers $n$ and $k$ ( $1 \le n \le 10; 1 \le k \le 10^9$ ).

The next line contains $n$ integers $a_1, a_2, \dots, a_n$ ( $0 = a_1 < a_2 < \dots < a_n \le 9$ ).

For each test case, print one integer — the minimum positive number of burles $s$ that cannot be represented with $k$ or fewer banknotes.