#include<bits/stdc++.h>
using namespace std;
int t,n,a[100005][2],a2[100005][2],top2,b2[100005],top,b[100005],ans;
string s1,s2,t1,t2;
int main(){
    freopen("edit.in","r",stdin);
    freopen("edit.out","w",stdout);
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    cin>>t;
    while(t--){
        cin>>n;
        cin>>s1>>s2>>t1>>t2;
        top=1;
        a[top][0]=0,a[top][1]=0;
        top2=1;
        a2[top2][0]=0,a2[top2][1]=0;
        ans=0;
        for(int i=0;i<n;i++){
            if(t1[i]=='1'){
                if(s1[i]=='0')a[top][0]++;
                else a[top][1]++;
                b[i]=top;
            }else{
                top++;
                a[top][0]=0;
                a[top][1]=0;
                b[i]=0;
            }
            if(t2[i]=='1'){
                if(s2[i]=='0')a2[top2][0]++;
                else a2[top2][1]++;
                b2[i]=top2;
            }else{
                top2++;
                a2[top2][0]=0;
                a2[top2][1]=0;
                b2[i]=0;
            }
        }
        for(int i=0;i<n;i++){
            if(t1[i]=='1'&&t2[i]=='1'){
                if(a[b[i]][0]>0&&a2[b2[i]][0]>0){
                    a[b[i]][0]--,a2[b2[i]][0]--;
                    ans++;
                }else if(a[b[i]][1]>0&&a2[b2[i]][1]>0){
                    a[b[i]][1]--,a2[b2[i]][1]--;
                    ans++;
                }
            }else if(t1[i]=='0'&&t2[i]=='1'){
                if(s1[i]=='1'&&a2[b2[i]][1]>0){
                    a2[b2[i]][1]--;
                    ans++;
                }else if(s1[i]=='0'&&a2[b2[i]][0]>0){
                    a2[b2[i]][0]--;
                    ans++;
                }
            }else if(t1[i]=='1'&&t2[i]=='0'){
                if(s2[i]=='1'&&a[b[i]][1]>0){
                    a[b[i]][1]--;
                    ans++;
                }else if(s2[i]=='0'&&a[b[i]][0]>0){
                    a[b[i]][0]--;
                    ans++;
                }
            }else{
                if(s1[i]==s2[i])ans++;
            }
        }
        cout<<ans<<"\n";
    }
    return 0;
}