#include<algorithm>
#include<fstream>
std::ifstream fin("edit.in");
std::ofstream fout("edit.out");
constexpr int N=100003;
char s1[N],s2[N],t1[N],t2[N];
int e1[N],e2[N];
int main()
{
	int t;
	fin>>t;
	while(t--)
	{
		int n,le1=0,le2=0,z1=0,z2=0;
		fin>>n>>s1>>s2>>t1>>t2,e1[le1++]=0,e2[le2++]=0;
		for(int i=0;i<n;i++)
			z1+=s1[i]=='1',z2+=s2[i]=='1';
		for(int i=1;i<n;i++)
		{
			if(t1[i-1]=='0'||t1[i]=='0')
				e1[le1++]=i;
			if(t2[i-1]=='0'||t2[i]=='0')
				e2[le2++]=i;
		}
		e1[le1++]=n,e2[le2++]=n;
		int p1=0,p2=0,x1=0,x2=0,ans=0;
		while(p1<le1&&p2<le2)
			if(e1[p1]==e2[p2])
			{
				ans+=std::min(x1,x2),x1=0,x2=0;
				for(int i=e1[p1];i<e1[p1+1];i++)
					x1+=s1[i]=='1';
				for(int i=e2[p2];i<e2[p2+1];i++)
					x2+=s2[i]=='1';
				p1++,p2++;
			}
			else if(e1[p1]<e2[p2])
			{
				x2=std::min(x2,e2[p2]-e1[p1]+x1);
				if(x2<x1)
					ans+=x2,x1=0,x2=0;
				for(int i=e1[p1];i<e1[p1+1];i++)
					x1+=s1[i]=='1';
				p1++;
			}
			else
			{
				x1=std::min(x1,e1[p1]-e2[p2]+x2);
				if(x1<x2)
					ans+=x1,x1=0,x2=0;
				for(int i=e2[p2];i<e2[p2+1];i++)
					x2+=s2[i]=='1';
				p2++;
			}
		fout<<n-z1-z2+2*ans<<'\n';
	}
	return 0;
}