#include<cstdio>
#define int long long
const int N=60;
struct LinearBasis{
	int a[N];
	bool clear(){for(int i=59;i+1;i--)a[i]=0;return true;}
	bool push(int x){
		for(int i=59;i+1;i--){
			if(!((x>>i)&1))continue;
			if(a[i]){x^=a[i];continue;}
			for(int j=0;j<i;j++)x^=a[j];
			for(int j=59;j>i;j--)if((a[j]>>i)&1)a[j]^=x;
			a[i]=x;return true;
		}
		return false;
	}
	int &operator [](int x){return a[x];}
	int qmin(int x){
		for(int i=59;i+1;i--)if((x>>i)&1)x^=a[i];
		return x;
	}
	int qmax(int x){
		for(int i=59;i+1;i--)if(!((x>>i)&1))x^=a[i];
		return x;
	}
};
LinearBasis A,B,C;
int read(){
	char ch=getchar();int nn=0,ssss=1;
	while(ch<'0'||ch>'9'){if(ch=='-')ssss*=-1;ch=getchar();}
	while(ch>='0'&&ch<='9'){nn=nn*10+(ch-'0');ch=getchar();}
	return nn*ssss;
}
bool solve(){
	int n=read();int m=read();int x=0;
	A.clear();B.clear();C.clear();
	for(int i=1;i<=n;i++){
		int a=read();int b=read();
		x^=a;A.push(a^b);
	}
	for(int i=1;i<=m;i++){
		int a=read();int b=read();
		x^=a;B.push(a^b);
	}
	for(int i=59;i+1;i--)if(A[i])C.push(B.qmin(A[i]));
	printf("%lld\n",C.qmax(B.qmin(x)));
	return true;
}
signed main(){
	int T=read();
	while(T--)solve();
}