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.
t = int(input())

while t:
 t = t-1
 n,d = input().split()
 n = list(n)
 d = int(d)
 
 n = list(map(int, n))
 
 x = []
 n.reverse()
 
 z = 0
 cc = d
 for c in n:
  # print(c, cc, z)
  if c > cc:
   z +=1
  else:
   x.append(c)
   cc = c
   
 x.reverse()
 
 for _ in range(z):
  x.append(d)
 x = list(map(str, x)) 
 print("".join(x))
t = int(input())

while t:
 t = t-1
 n,d = input().split()
 n = list(n)
 d = int(d)
 
 n = list(map(int, n))
 
 x = []
 n.reverse()
 
 z = 0
 cc = d
 for c in n:
  # print(c, cc, z)
  if c > cc:
   z +=1
  else:
   x.append(c)
   cc = c
   
 x.reverse()
 
 for _ in range(z):
  x.append(d)
 x = list(map(str, x)) 
 print("".join(x))