/* 3609 */

 #include <iostream>

 #include <sstream>

 #include <string>

 #include <map>

 #include <queue>

 #include <set>

 #include <stack>

 #include <vector>

 #include <deque>

 #include <bitset>

 #include <algorithm>

 #include <cstdio>

 #include <cmath>

 #include <ctime>

 #include <cstring>

 #include <climits>

 #include <cctype>

 #include <cassert>

 #include <functional>

 #include <iterator>

 #include <iomanip>

 using namespace std;

 //#pragma comment(linker,"/STACK:102400000,1024000")

 #define sti                set<int>

 #define stpii            set<pair<int, int> >

 #define mpii            map<int,int>

 #define vi                vector<int>

 #define pii                pair<int,int>

 #define vpii            vector<pair<int,int> >

 #define rep(i, a, n)     for (int i=a;i<n;++i)

 #define per(i, a, n)     for (int i=n-1;i>=a;--i)

 #define clr                clear

 #define pb                 push_back

 #define mp                 make_pair

 #define fir                first

 #define sec                second

 #define all(x)             (x).begin(),(x).end()

 #define SZ(x)             ((int)(x).size())

 #define lson            l, mid, rt<<1

 #define rson            mid+1, r, rt<<1|1

 #define LL long long

 void egcd(LL a, LL b, LL& g, LL& x, LL& y) {

     if (!b) {

         g = a;

         x = ;

         y = ;

     } else {

         egcd(b, a%b, g, y, x);

         y -= a/b*x;

     }

 }

 int inv(LL a, LL n) {

     LL g, x, y;

     egcd(a, n, g, x, y);

     if (g != )

         return -;

     return x%n== ? n:(x%n+n)%n;

 }

 int main() {

     ios::sync_with_stdio(false);

     #ifndef ONLINE_JUDGE

         freopen("data.in", "r", stdin);

         freopen("data.out", "w", stdout);

     #endif

     int t;

     LL a, m;

     LL ans;

     scanf("%d", &t);

     while (t--) {

         scanf("%lld%lld", &a, &m);

         ans = inv(a, m);

         if (ans == -) {

             puts ("Not Exist");

         } else {

             printf("%lld\n", ans);

         }

     }

     #ifndef ONLINE_JUDGE

         printf("time = %d.\n", (int)clock());

     #endif

     return ;

 }

 import sys

 import string

 from random import randint

 def GenData(fileName):

     with open(fileName, "w") as fout:

         t = 1000

         fout.write("%d\n" % (t))

         for tt in xrange(t):

             n = randint(1, 1000)

             m = randint(1, 1000)

             fout.write("%d %d\n" % (n, m))

 def MovData(srcFileName, desFileName):

     with open(srcFileName, "r") as fin:

         lines = fin.readlines()

     with open(desFileName, "w") as fout:

         fout.write("".join(lines))

 def CompData():

     print "comp"

     srcFileName = "F:\Qt_prj\hdoj\data.out"

     desFileName = "F:\workspace\cpp_hdoj\data.out"

     srcLines = []

     desLines = []

     with open(srcFileName, "r") as fin:

         srcLines = fin.readlines()

     with open(desFileName, "r") as fin:

         desLines = fin.readlines()

     n = min(len(srcLines), len(desLines))-1

     for i in xrange(n):

         ans2 = int(desLines[i])

         ans1 = int(srcLines[i])

         if ans1 > ans2:

             print "%d: wrong" % i

 if __name__ == "__main__":

     srcFileName = "F:\Qt_prj\hdoj\data.in"

     desFileName = "F:\workspace\cpp_hdoj\data.in"

     GenData(srcFileName)

     MovData(srcFileName, desFileName)