Hidden Digits

You are given a sequence of $n$ digits $d_0$, $d_1$, \dots, $d_{n-1}$. Find the minimum positive integer $x$ such that for all $0 \le i < n$, the decimal representation of $x + i$ contains the digit $d_i$.

The input contains multiple test cases. The first line contains the number of test cases $t$ ($1 \le t \le 10^5$). The test cases follow. The first line of each test case contains a single integer $n$ ($1 \le n \le 10^6$). The second line contains a string of $n$ digits $d_0 d_1 \ldots d_{n-1}$ ($0 \le d_i \le 9$). The sum of $n$ over all test cases does not exceed $10^6$.

For each test case, print a single integer $x$, the smallest positive integer such that the decimal representation of $x+i$ contains the digit $d_i$ for all $0 \le i < n$.