Chef Leonardo has a decimal integer $N$ and a non-zero decimal digit $d$. $N$ does not contain the digit zero; specifically, $N$ should always be treated as a decimal integer without leading zeroes.
Chef likes $d$ and does not like any other digit, so he decided to change $N$. He may apply the following operation any number of times (including zero): append the digit $d$ to the decimal representation of $N$ ($d$ becomes the least significant digit of $N$), then remove one occurrence of one digit from the decimal representation of $N$.
Chef has already changed a lot of numbers and he got bored. Now, he wants to know the smallest possible value of $N$ which can be obtained by performing the operation described above. Can you help him?

-----Input-----
- The first line of the input contains a single integer $T$ denoting the number of test cases. The description of $T$ test cases follows.
- The first and only line of each test case contains two space-separated integers $N$ and $d$.

-----Output-----
For each test case, print a single line containing one integer - the minimum number Chef can obtain.

-----Constraints-----
- $1 \le T \le 1,000$
- $1 \le N \le 10^{18}$
- $N$ does not contain the digit $0$
- $1 \le d \le 9$

-----Subtasks-----
Subtask #1 (40 points):
- $1 \le T \le 100$
- $1 \le N \le 10^9$
Subtask #2 (60 points): original constraints

-----Example Input-----
3
35 4
42 4
24 9

-----Example Output-----
34
24
24

-----Explanation-----
Example case 1: Chef can remove the digit $5$ and add $4$ to the end of $N$. Then, $N$ becomes $34$.
Example case 2: Chef can remove the digit $4$ from the beginning of $N$, add $4$ to the end of $N$ and get $N = 24$.
Example case 3: Chef cannot make his number any smaller.

```python

USER_FILENAME = "<user_code>"
import sys, json, builtins
import math, heapq, bisect, itertools, functools, collections, statistics, fractions, decimal, operator, array, random, re, string, os, pathlib
try:
    import resource as _res
except Exception:
    _res = None
from collections import Counter, defaultdict, deque, OrderedDict
from functools import lru_cache, reduce
from itertools import accumulate, permutations, combinations, product
from math import gcd, ceil, floor, sqrt
from decimal import Decimal
try:
    from typing import *
except Exception:
    pass
try:
    sys.setrecursionlimit(1_000_000)
except Exception:
    pass
try:
    import site as _site
    try:
        _sys_sites = _site.getsitepackages() if hasattr(_site, "getsitepackages") else []
        for _p in _sys_sites:
            if _p and _p not in sys.path:
                sys.path.append(_p)
    except Exception:
        pass
    try:
        _usp = _site.getusersitepackages()
        if isinstance(_usp, str):
            _usp = [_usp]
        for _p in _usp:
            if _p and _p not in sys.path:
                sys.path.append(_p)
    except Exception:
        pass
except Exception:
    pass

ns = {"__name__": "__main__"}
for _k, _v in list(globals().items()):
    if not _k.startswith("_"):
        ns[_k] = _v
_CODE = '# cook your dish here\nt=int(input())\nfor _ in range(t):\n n,d=input().split(" ")\n q=int(d)\n k=[]\n for i in n:\n  k.append(i)\n   \n k2=k[::]\n\n min=int(d)\n for j in range(len(k2)-1,-1,-1):\n  if int(k2[j])>min:\n    k2.pop(j)\n  else:\n   min=int(k2[j])\n \n\n print(*k2,sep="",end="")\n print(d*(len(k)-len(k2)))'
_co = compile(_CODE, USER_FILENAME, "exec")
exec(_co, ns, ns)

```

Measured memory_bytes: 13253