Ashley wrote a random number generator code.
Due to some reasons, the code only generates random positive integers which are not evenly divisible by 10. She gives $N$ and $S$ as input to the random number generator. The code generates a random number with number of digits equal to $N$ and sum of digits equal to $S$. The code returns -1 if no number can be generated. Print "-1" in such cases (without quotes). Else print the minimum possible product of digits of the random number generated.
-----Input:-----
- First line will contain a single integer $T$, the number of testcases. 
- Each testcase consists of two space separated integers, $N$ and $S$. 
-----Output:-----
For each testcase, output the answer on a new line.
-----Constraints-----
- $1 \leq T \leq 10^5$
- $1 \leq N \leq 18$
- $1 \leq S \leq 5 * N$
-----Sample Input:-----
2
1 5
2 2
-----Sample Output:-----
5
1
-----EXPLANATION:-----
In first testcase, the only possible number of length 1 having digit sum 5 is 5. And it's product of digits is 5. 
In second testcase,  only possible two digit number as a generator output is 11(as 20 is divisible by 10, it is never generated) and product of it's digits is 1.
for t in range(int(input())):
    n, s = [int(i) for i in input().split()]
    if (n == 1):
        print(s)
        continue

    if (s < 2):
        print(-1)
        continue

    if (n == 2):
        print(s - 1)
        continue

    l = [0 for i in range(n)]
    s -= 18
    l[0] = 9
    l[-1] = 9
    if (s <= 0):
        print(0)
        continue

    res = 1
    for i in range(n):
        temp = min(s, (9 - l[i]))
        l[i] += temp
        s -= temp
        res = res * l[i]
        i += 1
    print(res)
for t in range(int(input())):
    n, s = [int(i) for i in input().split()]
    if (n == 1):
        print(s)
        continue

    if (s < 2):
        print(-1)
        continue

    if (n == 2):
        print(s - 1)
        continue

    l = [0 for i in range(n)]
    s -= 18
    l[0] = 9
    l[-1] = 9
    if (s <= 0):
        print(0)
        continue

    res = 1
    for i in range(n):
        temp = min(s, (9 - l[i]))
        l[i] += temp
        s -= temp
        res = res * l[i]
        i += 1
    print(res)