#include <iostream>
#include <string.h>
#include <stdio.h>
#include <algorithm>
#include <cmath>
using namespace std;
typedef long long LL;
const double PI = acos(-1.0);

LL n , _ ,cas = 1 , a[12] , r[12] ;

void e_gcd( LL a ,LL b , LL &d , LL &x, LL &y  )
{
    if( b == 0 ){ x = 1 , y = 0 , d = a ; return ; }
    e_gcd( b, a%b , d, y ,x ) ;
    y -= x*( a/b );
}

LL gcd( LL a , LL b ){ return b == 0 ? a : gcd( b , a%b ) ;}


void run()
{
    LL lcm = 1 ;
    cin >> n ;
    for( int i = 0 ; i < n ; ++i ){
        cin >> a[i] ;
        lcm = lcm / gcd( lcm , a[i] ) * a[i] ;
    }
    for( int i = 0 ; i < n ; ++i ){
        cin >> r[i];
    }
    for( int i = 1 ; i < n ; ++i ) {
        LL d , x , y , A = a[0] , B = a[i] , c = r[i] - r[0] ;
        e_gcd(A,B,d,x,y) ;
        if( c % d ) { cout << "-1" <<endl ; return ; }
        LL b1 = B / d ;
        x *= c / d;
        x = ( x % b1 + b1 ) % b1;
        r[0] = a[0] * x + r[0] ;
        a[0] = a[0] *( a[i] / d );
    }
    if( r[0] == 0 )
        cout<< lcm <<endl ;
    else
        cout << r[0] <<endl;
}

int main()
{
    #ifdef LOCAL
        freopen("in.txt","r",stdin);
    #endif // LOCAL
    ios::sync_with_stdio(0);
    cin >> _ ;
    while( _-- ){
        cout <<"Case "<< cas++ << ": ";
        run();
    }

}