"""

https://yukicoder.me/problems/no/1140

"""

from sys import stdin
import math

def Sieve(n): #n以下の素数全列挙(O(nloglogn)) retは素数が入ってる。divlisはその数字の素因数が一つ入ってる

    ret = []
    divlis = [-1] * (n+1) #何で割ったかのリスト(初期値は-1)
    
    flag = [True] * (n+1)
    flag[0] = False
    flag[1] = False

    ind = 2
    while ind <= n:

        if flag[ind]:
            ret.append(ind)

            ind2 = ind ** 2

            while ind2 <= n:
                flag[ind2] = False
                divlis[ind2] = ind
                ind2 += ind

        ind += 1

    return ret,divlis

plis,divlis = Sieve(6000000)

pset = set(plis)

TT = int(stdin.readline())

ANS = []

for _ in range(TT):

    A,P = map(int,stdin.readline().split())
    
    if P not in pset:
        ANS.append(-1)
    elif A % P == 0:
        ANS.append(0)
    else:
        ANS.append(1)

print (*ANS,sep="\n")