#include <bits/stdc++.h>
#define endl '\n'
using namespace std;
const int N=1e5+3;
int T,n,ans,tot1,tot2;
string s1,s2,f1,f2;
bool g1[N],g2[N];
struct line{
    int l=0,r=0,c[2]={0,0};
};
line t1[N],t2[N];
int cnt1[2],cnt2[2];
int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);cout.tie(0);
    freopen("edit.in","r",stdin);
    freopen("edit.out","w",stdout);
    cin>>T;
    while(T--){
        memset(g1,0,sizeof(g1));
        memset(g2,0,sizeof(g2));
        memset(cnt1,0,sizeof(cnt1));
        memset(cnt2,0,sizeof(cnt2));
        cin>>n>>s1>>s2>>f1>>f2;
        for(int i=1;i<=n;i++){
			t1[i].l=t1[i].r=t1[i].c[0]=t1[i].c[1]=0;
			t2[i].l=t2[i].r=t2[i].c[0]=t2[i].c[1]=0;
		}
        ans=tot1=tot2=0;
        t1[1].l=0;
        t2[1].l=0;
        for(int i=0;i<n;i++){
            if(f1[i]!='0')cnt1[s1[i]-'0']++;
            if(f2[i]!='0')cnt2[s2[i]-'0']++;
            if(f1[i]=='0'){
                g1[i]=1;
                if(cnt1[0]!=0||cnt1[1]!=0){
					tot1++;
					t1[tot1].r=i-1,t1[tot1].c[0]=cnt1[0],t1[tot1].c[1]=cnt1[1];
					cnt1[0]=0,cnt1[1]=0;
				}
                tot1++;
                t1[tot1].l=i,t1[tot1].r=i;
                t1[tot1].c[s1[i]-'0']++;
                if(i+1!=n)t1[tot1+1].l=i+1;
            }
            if(f2[i]=='0'){
                g2[i]=1;
                if(cnt2[0]!=0||cnt2[1]!=0){
					tot2++;
					t2[tot2].r=i-1,t2[tot2].c[0]=cnt2[0],t2[tot2].c[1]=cnt2[1];
					cnt2[0]=0,cnt2[1]=0;
				}
                tot2++;
                t2[tot2].l=i,t2[tot2].r=i;
                t2[tot2].c[s2[i]-'0']++;
                if(i+1!=n)t2[tot2+1].l=i+1;
            }
            if(i==n-1){
                if(cnt1[0]!=0||cnt1[1]!=0){
					tot1++;
					t1[tot1].r=i,t1[tot1].c[0]=cnt1[0],t1[tot1].c[1]=cnt1[1];
					cnt1[0]=0,cnt1[1]=0;
				}
                if(cnt2[0]!=0||cnt2[1]!=0){
					tot2++;
					t2[tot2].r=i,t2[tot2].c[0]=cnt2[0],t2[tot2].c[1]=cnt2[1];
					cnt2[0]=0,cnt2[1]=0;
				}
			}
        }
        // for(int i=1;i<=tot1;i++){
		// 	cout<<t1[i].l<<" "<<t1[i].r<<" "<<t1[i].c[0]<<" "<<t1[i].c[1]<<endl;
		// }
		// cout<<endl;
        // for(int i=1;i<=tot2;i++){
		// 	cout<<t2[i].l<<" "<<t2[i].r<<" "<<t2[i].c[0]<<" "<<t2[i].c[1]<<endl;
		// }
        //A
        // bool flag=1,tt=s1[0]-'0';
        // for(int i=1;i<n;i++){
        //     if(s1[i]-'0'!=tt){
        //         flag=0;
        //     }
        // }
        // if(flag==1){
        //     for(int i=0;i<n;i++){
        //         if(s2[i]-'0'==tt){
        //             ans++;
        //         }
        //     }
        //     cout<<ans<<endl;
        //     continue;
        // }

        int xxx=0;
        int pos1=1,pos2=1,r1=t1[1].r,r2=t2[1].r;
        while(pos1<=tot1||pos2<=tot2){
			r1=t1[pos1].r,r2=t2[pos2].r;
            if(pos1==tot1&&pos2==tot2){
                xxx++;
            }
            if(xxx==3){
                break;
            }
            //cout<<pos1<<" "<<pos2<<endl;
			//cout<<r1<<" "<<r2<<" ";
            // cout<<ans<<endl;
            //cout<<t1[pos1].c[0]<<" "<<t2[pos2].c[0]<<endl;
            //cout<<t1[pos1].c[1]<<" "<<t2[pos2].c[1]<<endl;
            if(r1<=r2){
                ans+=min(t1[pos1].c[1],t2[pos2].c[1]);
                ans+=min(t1[pos1].c[0],t2[pos2].c[0]);
                //1
                if(t1[pos1].c[1]<=t2[pos2].c[1]){
                    t2[pos2].c[1]-=t1[pos1].c[1];
                }else{
                    t2[pos2].c[0]-=(t1[pos1].c[1]-t2[pos2].c[1]);
                    t2[pos2].c[1]=0;
                }
                //0
                if(t1[pos1].c[0]<=t2[pos2].c[0]){
                    t2[pos2].c[0]-=t1[pos1].c[0];
                }else{
                    t2[pos2].c[1]-=(t1[pos1].c[0]-t2[pos2].c[0]);
                    t2[pos2].c[0]=0;
                }
                pos1++;
                if(t2[pos2].c[0]+t2[pos2].c[1]==0)pos2++;
            }else if(r1>r2){
                ans+=min(t1[pos1].c[1],t2[pos2].c[1]);
                ans+=min(t1[pos1].c[0],t2[pos2].c[0]);
                //1
                if(t2[pos2].c[1]<=t1[pos1].c[1]){
                    t1[pos1].c[1]-=t2[pos2].c[1];
                }else{
                    t1[pos1].c[0]-=(t2[pos2].c[1]-t1[pos1].c[1]);
                    t1[pos1].c[1]=0;
                }
                //0
                if(t2[pos2].c[0]<=t1[pos1].c[0]){
                    t1[pos1].c[0]-=t2[pos2].c[0];
                }else{
                    t1[pos1].c[1]-=(t2[pos2].c[0]-t1[pos1].c[0]);
                    t1[pos1].c[0]=0;
                }
                pos2++;
                if(t1[pos1].c[0]+t1[pos1].c[1]==0)pos1++;
            }
            pos1=min(pos1,tot1);
            pos2=min(pos2,tot2);
            //cout<<ans<<endl;
        }
        cout<<ans<<endl;
    }
    return 0;
}