1 #include <cstdio>
 2 #include <cstring>
 3 #include <iostream>
 4 #include <stack>
 5 #include <queue>
 6 #include <map>
 7 #include <algorithm>
 8 #include <vector>
 9 
10 using namespace std;
11 
12 const int maxn = 1000005;
13 
14 typedef long long LL;
15 
16 LL gcd( LL a,LL b)
17 {
18     if(b == 0) return a;
19    else  return gcd(b,a%b);
20 }
21 
22 LL ex_gcd(LL a,LL b,LL &x,LL &y)
23 {
24    if(b == 0){
25         x = 1;
26         y = 0;
27         return a;
28    }
29    LL r = ex_gcd(b,a%b,x,y);
30    LL t = x;
31       x = y;
32       y = t - a/b*y;
33       return r;
34 }
35 LL aa[20],r[20];
36 
37 int main()
38 {
39     LL i,ans,a,b,c,d,k,x,y,n,m;
40     LL T;
41     cin>>T;
42     int cas = 0;
43     while(T--){
44         cin>>m;
45         cas++;
46         bool flag = 1;
47         LL lcm = 1;
48         for(i=1;i<=m;i++){
49             cin>>aa[i];
50             lcm = lcm/gcd(lcm,aa[i])*aa[i];
51         }
52         for( i=1;i<=m;i++){
53             cin>>r[i];
54         }
55         printf("Case %d: ",cas);
56         for( i=2;i<=m;i++){
57             a = aa[1];
58             b = aa[i];
59             c = r[i] - r[1];
60             d = ex_gcd(a,b,x,y);
61             if(c%d!=0){
62                 flag = 0;
63                 break;
64             }
65             LL t = b/d;
66                  x = (x*(c/d)%t+t)%t;
67                  r[1] = aa[1]*x + r[1];
68                  aa[1] = aa[1]*(aa[i]/d);
69         }
70         if(!flag){
71             puts("-1");
72             continue;
73         }
74 
75         if(r[1]){
76            printf("%lld\n",r[1]);
77            continue;
78         }
79 
80         printf("%lld\n",lcm);
81     }
82 
83     return 0;
84 }