Your friend Jeff Zebos has been trying to run his new online company, but it's not going very well. He's not getting a lot of sales on his website which he decided to call Azamon. His big problem, you think, is that he's not ranking high enough on the search engines. If only he could rename his products to have better names than his competitors, then he'll be at the top of the search results and will be a millionaire.

After doing some research, you find out that search engines only sort their results lexicographically. If your friend could rename his products to lexicographically smaller strings than his competitor's, then he'll be at the top of the rankings!

To make your strategy less obvious to his competitors, you decide to swap no more than two letters of the product names.

Please help Jeff to find improved names for his products that are lexicographically smaller than his competitor's!

Given the string s representing Jeff's product name and the string c representing his competitor's product name, find a way to swap at most one pair of characters in s (that is, find two distinct indices i and j and swap s_i and s_j) such that the resulting new name becomes strictly lexicographically smaller than c, or determine that it is impossible.

Note: String a is strictly lexicographically smaller than string b if and only if one of the following holds:

  * a is a proper prefix of b, that is, a is a prefix of b such that a ≠ b; 
  * There exists an integer 1 ≤ i ≤ min{(|a|, |b|)} such that a_i < b_i and a_j = b_j for 1 ≤ j < i. 

Input

The first line of input contains a single integer t (1 ≤ t ≤ 1500) denoting the number of test cases. The next lines contain descriptions of the test cases.

Each test case consists of a single line containing two space-separated strings s and c (2 ≤ |s| ≤ 5000, 1 ≤ |c| ≤ 5000). The strings s and c consists of uppercase English letters.

It is guaranteed that the sum of |s| in the input is at most 5000 and the sum of the |c| in the input is at most 5000.

Output

For each test case, output a single line containing a single string, which is either

  * the new name which is obtained after swapping no more than one pair of characters that is strictly lexicographically smaller than c. In case there are many possible such strings, you can output any of them; 
  * three dashes (the string "---" without quotes) if it is impossible. 

Example

Input


3
AZAMON APPLE
AZAMON AAAAAAAAAAALIBABA
APPLE BANANA


Output


AMAZON
---
APPLE

Note

In the first test case, it is possible to swap the second and the fourth letters of the string and the resulting string "AMAZON" is lexicographically smaller than "APPLE".

It is impossible to improve the product's name in the second test case and satisfy all conditions.

In the third test case, it is possible not to swap a pair of characters. The name "APPLE" is lexicographically smaller than "BANANA". Note that there are other valid answers, e.g., "APPEL". 
import sys
import os
from io import BytesIO, IOBase

#########################
# imgur.com/Pkt7iIf.png #
#########################

# returns the list of prime numbers less than or equal to n:
'''def sieve(n):
    if n < 2: return list()
    prime = [True for _ in range(n + 1)]
    p = 3
    while p * p <= n:
        if prime[p]:
            for i in range(p * 2, n + 1, p):
                prime[i] = False
        p += 2
    r = [2]
    for p in range(3, n + 1, 2):
        if prime[p]:
            r.append(p)
    return r'''

# returns all the divisors of a number n(takes an additional parameter start):
'''def divs(n, start=1):
    divisors = []
    for i in range(start, int(math.sqrt(n) + 1)):
        if n % i == 0:
            if n / i == i:
                divisors.append(i)
            else:
                divisors.extend([i, n // i])
    return divisors'''

# returns the number of factors of a given number if a primes list is given:
'''def divn(n, primes):
    divs_number = 1
    for i in primes:
        if n == 1:
            return divs_number
        t = 1
        while n % i == 0:
            t += 1
            n //= i
        divs_number *= t
    return divs_number'''

# returns the leftmost and rightmost positions of x in a given list d(if x isnot present then returns (-1,-1)):
'''def flin(d, x, default=-1):
    left = right = -1
    for i in range(len(d)):
        if d[i] == x:
            if left == -1: left = i
            right = i
    if left == -1:
        return (default, default)
    else:
        return (left, right)'''

# returns (b**p)%m 
'''def modpow(b,p,m):
    res=1
    b=b%m
    while(p):
        if p&1:
            res=(res*b)%m
        b=(b*b)%m
        p>>=1
    return res'''

# if m is a prime this can be used to determine (1//a)%m or modular multiplicative inverse of a number a
'''def mod_inv(a,m):
    return modpow(a,m-2,m)'''

# returns the ncr%m for (if m is a prime number) for very large n and r
'''def ncr(n,r,m):
    res=1
    if r==0:
        return 1
    if n-r<r:
        r=n-r
    p,k=1,1
    while(r):
        res=((res%m)*(((n%m)*mod_inv(r,m))%m))%m
        n-=1
        r-=1
    return res'''

# returns ncr%m (if m is a prime number and there should be a list fact which stores the factorial values upto n):
'''def ncrlis(n,r,m):
    return (fact[n]*(mod_inv(fact[r],m)*mod_inv(fact[n-r],m))%m)%m'''

#factorial list which stores factorial of values upto n:
'''mx_lmt=10**5+10
fact=[1 for i in range(mx_lmt)]
for i in range(1,mx_lmt):
    fact[i]=(i*fact[i-1])%mod'''

#count xor of numbers from 1 to n:
'''def xor1_n(n):
    d={0:n,1:1,2:n+1,3:0}
    return d[n&3]'''

def cel(n, k): return n // k + (n % k != 0)
def ii(): return int(input())
def mi(): return map(int, input().split())
def li(): return list(map(int, input().split()))
def lcm(a, b): return abs(a * b) // math.gcd(a, b)
def prr(a, sep=' '): print(sep.join(map(str, a)))
def dd(): return defaultdict(int)
def ddl(): return defaultdict(list)
def ddd(): return defaultdict(defaultdict(int))
 

# region fastio
 
BUFSIZE = 8192
 
 
class FastIO(IOBase):
	newlines = 0
 
	def __init__(self, file):
		self._fd = file.fileno()
		self.buffer = BytesIO()
		self.writable = "x" in file.mode or "r" not in file.mode
		self.write = self.buffer.write if self.writable else None
 
	def read(self):
			while True:
					b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
					if not b:
							break
					ptr = self.buffer.tell()
					self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
			self.newlines = 0
			return self.buffer.read()
 
	def readline(self):
			while self.newlines == 0:
					b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
					self.newlines = b.count(b"\n") + (not b)
					ptr = self.buffer.tell()
					self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
			self.newlines -= 1
			return self.buffer.readline()
 
	def flush(self):
			if self.writable:
					os.write(self._fd, self.buffer.getvalue())
					self.buffer.truncate(0), self.buffer.seek(0)
 
 
class IOWrapper(IOBase):
	def __init__(self, file):
			self.buffer = FastIO(file)
			self.flush = self.buffer.flush
			self.writable = self.buffer.writable
			self.write = lambda s: self.buffer.write(s.encode("ascii"))
			self.read = lambda: self.buffer.read().decode("ascii")
			self.readline = lambda: self.buffer.readline().decode("ascii")
 

sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
input = lambda: sys.stdin.readline().rstrip("\r\n")

from collections import defaultdict 
#from collections import deque
#from collections import OrderedDict
#from math import gcd
#import time
#import itertools
#import timeit
#import random
#from bisect import bisect_left as bl
#from bisect import bisect_right as br
#from bisect import insort_left as il
#from bisect import insort_right as ir
#from heapq import *
#mod=998244353
#mod=10**9+7

for _ in range(ii()):
    s,c=input().split()
    s=list(s)
    c=list(c)
    if s<c:
        print(''.join(s))
        continue
    idx=0
    s2=sorted(s)
    for i in range(len(s)):
        if s[i]==s2[idx]:
            idx+=1
            continue
        if s[i]>s2[idx]:
            r=''.join(s).rfind(s2[idx])
            s[i],s[r]=s[r],s[i]
            break
    if s<c:
        print(''.join(s))
    else:
        print('---')
