#include<bits/stdc++.h>
using namespace std;
#define rd(i,n) for(int i=0;i<n;i++)
#define rp(i,n) for(int i=1;i<=n;i++)
#define rep(i,a,b) for(int i=a;i<=b;i++)
#define per(i,a,b) for(int i=b;i>=a;i--)
#define vt vector
#define pb push_back
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef long double ld;
int n;
string s1,s2,t1,t2;
inline void solve(){
    cin>>n;
    cin>>s1>>s2>>t1>>t2;
    int ans=0,cnt=0;
    rd(i,n){
        cnt+=(s1[i]=='1');
        cnt+=(s2[i]=='1');
    }
    int c1=0,c2=0,m1=0,m2=0,v1=-1,v2=-1;
    while(c1<n&&t1[c1]!='0')m1+=(s1[c1]=='1'),c1++;
    while(c2<n&&t2[c2]!='0')m2+=(s2[c2]=='1'),c2++;
    while(c1!=n||c2!=n){
        int x=min(m1,m2);
        x=min(x,(min(c1,c2)-max(v1,v2)-1));
        x=max(x,0);
        ans+=x,m1-=x,m2-=x;
        if(c1==c2){
            ans+=(s1[c1]=='1'&&s2[c2]=='1');
            v1=c1,v2=c2,c1++,c2++,m1=0,m2=0;
            while(c1<n&&t1[c1]!='0')m1+=(s1[c1]=='1'),c1++;
            while(c2<n&&t2[c2]!='0')m2+=(s2[c2]=='1'),c2++;
        }else if(c1<c2){
            if(s1[c1]=='1'&&m2)ans++,m2--;
            v1=c1,c1++,m1=0;
            while(c1<n&&t1[c1]!='0')m1+=(s1[c1]=='1'),c1++;
        }else{
            if(s2[c2]=='1'&&m1)ans++,m1--;
            v2=c2,c2++,m2=0;
            while(c2<n&&t2[c2]!='0')m2+=(s2[c2]=='1'),c2++;
        }
    }
 //   cout<<m1<<' '<<m2<<endl;
    int x=min(m1,m2);
    x=min(x,(min(c1,c2)-max(v1,v2)-1));
    x=max(x,0);
    ans+=x;
 //   cout<<ans<<endl;
    cout<<n-(cnt-2*ans)<<'\n';
}
signed main(){
    freopen("edit.in","r",stdin);
    freopen("edit.out","w",stdout);
    ios::sync_with_stdio(false);
    cin.tie(0);cout.tie(0);
    int t;
    cin>>t;
    rd(_,t)solve();
    return 0;
}
//Rain Rain Rain
//g++ edit.cpp -o edit -O2 -std=c++14 -static
//g++ edit.cpp -o edit -O2 -std=c++14 -static -fsanitize=undefined -fsanitize=address -D_GLIBCXX_DEBUG -Wall -Wextra -Wshadow