#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
using namespace std;
typedef long long ll;
const int N=15;
inline ll read(){
    char c=getchar();ll x=0,f=1;
    while(c<‘0‘||c>‘9‘){if(c==‘-‘)f=-1;c=getchar();}
    while(c>=‘0‘&&c<=‘9‘){x=x*10+c-‘0‘;c=getchar();}
    return x*f;
}
ll r,n,a[N],m[N];
void exgcd(ll a,ll b,ll &d,ll &x,ll &y){
    if(b==0) d=a,x=1,y=0;
    else exgcd(b,a%b,d,y,x),y-=(a/b)*x;
}
void exCRT(){
    ll m1,a1,m2,a2,flag=0;
    m1=m[1];a1=a[1];
    for(int i=2;i<=n;i++){
        m2=m[i];a2=a[i];
        ll d,t1,t2;
        exgcd(m1,m2,d,t1,t2);
        if((a2-a1)%d) {flag=1;break;}
        t1*=(a2-a1)/d;
        m2/=d;
        t1=(t1%m2+m2)%m2;
        a1=t1*m1+a1;
        m1*=m2;
    }
    if(flag||a1>r) puts("0");
    else printf("%lld\n",(r-a1)/m1+1+(a1==0?-1:0));
}
int main(){
    freopen("in","r",stdin);
    int T=read();
    while(T--){
        r=read();n=read();
        for(int i=1;i<=n;i++) m[i]=read();
        for(int i=1;i<=n;i++) a[i]=read();
        exCRT();
    }
}