Consider the following process. You have a binary string (a string where each character is either 0 or 1) w of length n and an integer x. You build a new binary string s consisting of n characters. The i-th character of s is chosen as follows:

  * if the character w_{i-x} exists and is equal to 1, then s_i is 1 (formally, if i > x and w_{i-x} =  1, then s_i =  1); 
  * if the character w_{i+x} exists and is equal to 1, then s_i is 1 (formally, if i + x ≤ n and w_{i+x} =  1, then s_i =  1); 
  * if both of the aforementioned conditions are false, then s_i is 0. 



You are given the integer x and the resulting string s. Reconstruct the original string w.

Input

The first line contains one integer t (1 ≤ t ≤ 1000) — the number of test cases.

Each test case consists of two lines. The first line contains the resulting string s (2 ≤ |s| ≤ 10^5, each character of s is either 0 or 1). The second line contains one integer x (1 ≤ x ≤ |s| - 1).

The total length of all strings s in the input does not exceed 10^5.

Output

For each test case, print the answer on a separate line as follows:

  * if no string w can produce the string s at the end of the process, print -1; 
  * otherwise, print the binary string w consisting of |s| characters. If there are multiple answers, print any of them. 

Example

Input


3
101110
2
01
1
110
1


Output


111011
10
-1
import math 
from collections import deque
import sys


sys.setrecursionlimit(10**4) 

def Divisors(n) : 
	
	l=[]
	i = 2
	while i <= math.sqrt(n): 
		
		if (n % i == 0) : 
			
			
			if (n // i == i) : 
				l.append(i)
			else : 
				l.append(i)
				l.append(n//i)
		i = i + 1
	return l

def SieveOfEratosthenes(n): 
	
	l=[]
	
	prime = [True for i in range(n+1)] 
	p = 2
	while (p * p <= n): 
		
		if (prime[p] == True): 
			
			for i in range(p * p, n+1, p): 
				prime[i] = False
		p += 1
	
	for p in range(2, n+1): 
		if prime[p]: 
			l.append(p)
	
	return l		

def primeFactors(n): 
	
	l=[]
	
	while n % 2 == 0: 
		l.append(2) 
		n = n / 2
		
	for i in range(3,int(math.sqrt(n))+1,2): 
		
		while n % i== 0: 
			l.append(i) 
			n = n / i 
			
	if n > 2: 
		l.append(n)
	
	return(l)	
		

def Factors(n) : 
	
	
	result = []
	
	for i in range(2,(int)(math.sqrt(n))+1) : 

		if (n % i == 0) : 
		    
			if (i == (n/i)) : 
				result.append(i)
			else : 
			    result.append(i)
			    result.append(n//i)
		
	result.append(1)
	
	return result

def maxSubArraySum(a): 
	
	max_so_far = 0
	max_ending_here = 0
	size=len(a)
	
	for i in range(0, size): 
		max_ending_here = max_ending_here + a[i] 
		if (max_so_far < abs(max_ending_here)): 
			max_so_far = max_ending_here 

	return max_so_far 

def longestsubarray(arr, n, k): 
    current_count = 0
      
    # this will contain length of  
    # longest subarray found 
    max_count = 0
  
    for i in range(0, n, 1): 
        if (arr[i] % k != 0): 
            current_count += 1
        else: 
            current_count = 0
        max_count = max(current_count,  
                            max_count) 
      
    return max_count 
    
#print(SieveOfEratosthenes(100))
#print(Divisors(100))
#print(primeFactors(100))
#print(Factors(100))
#print(maxSubArraySum(a))
 

def main():
    
    s=input()
    s1=""
    x=int(input())
    l=['1' for i in range(0,len(s))]
    n=len(s)
    for i in range(n-1,-1,-1):
        if s[i]=='0' :
            if i+x < n :
                l[i+x]='0'
            if i-x>=0 :
                l[i-x]='0'
    l1=['0' for i in range(0,n)]
    for i in range(0,n):
        if l[i]=='1':
            if i+x < n :
                l1[i+x]='1'
            if i-x>=0 :
                l1[i-x]='1'
    s2=""
    for i in range(0,n):
        s2+=l1[i]
    if s==s2:
        for i in range(0,n):
            print(l[i],end="")
        print()
    else:
        print(-1)
    
    
    
    
t=int(input())
for i in range(0,t):
    main()