#include <bits/stdc++.h>
using namespace std;
#define int long long
#define M 200005 // 2e5
#define mid ((L+R)/2)
#define p1 first
#define p2 second
#define make_pair P
const int inf=1e18+7;
inline void read(int &x) {
	x=0; char ch=getchar(); int fg=1;
	while(ch<'0'||ch>'9') fg=(ch=='-'?-1:fg),ch=getchar();
	while(ch>='0'&&ch<='9') x=x*10+ch-'0',ch=getchar();
	x*=fg;
}
inline void write(int x) {
	if(x<0) putchar('-'),x=-x;
	if(x>9) write(x/10);
	putchar(x%10+'0');
}
int TT,n,rr,ans;
int a[2][M];
// int cc[10];
int sz[2],s1[2][M],l[2][M],r[2][M];
int c0[2],c1[2];
string s,t,S,T,ss;
void CLEAR() {
	sz[0]=sz[1]=0;
	ans=0;
}
int V(int L,int R,int f1,int f2) {
	int cc1=s1[f1][R]-(L?s1[f1][L-1]:0);
	if(f2) return cc1; return (R-L+1)-cc1;
}
void Solve() {
	int z0=0,z1=0,tg,nr=-1,nw;
	c0[0]=c0[1]=c1[0]=c1[1]=0,tg=-1;
	while(z0<sz[0]||z1<sz[1]) {
		if(!z0||nr==r[0][z0]) z0++,c0[0]=V(nr+1,r[0][z0],0,0),c1[0]=V(nr+1,r[0][z0],0,1);
		if(!z1||nr==r[1][z1]) z1++,c0[1]=V(nr+1,r[1][z1],1,0),c1[1]=V(nr+1,r[1][z1],1,1);
		if(r[0][z0]>r[1][z1]) tg=0; else tg=1;
		nw=min(r[0][z0],r[1][z1]);
		// cout<<z0<<' '<<z1<<' '<<nr<<' '<<nw<<' '<<ans<<"  "<<c0[0]<<' '<<c1[0]<<' '<<c0[1]<<' '<<c1[1]<<endl;
		for(int i=nr+1;i<=nw;i++) {
			if(c1[tg^1]) {
				c1[tg^1]--;
				if(c1[tg]) c1[tg]--,ans++;
				else c0[tg]--;
			} else {
				c0[tg^1]--;
				if(c0[tg]) c0[tg]--,ans++;
				else c1[tg]--;
			}
		}
		// cout<<z0<<' '<<z1<<' '<<nr<<' '<<nw<<' '<<ans<<"  "<<c0[0]<<' '<<c1[0]<<' '<<c0[1]<<' '<<c1[1]<<endl;
		nr=nw;
	}
}
signed main() {
	freopen("edit.in","r",stdin);
	freopen("edit.out","w",stdout);
	ios::sync_with_stdio(false);
	cin.tie(0),cout.tie(0);
	cin>>TT;
	while(TT--) {
		CLEAR();
		cin>>n>>s>>t>>S>>T,ss=s,rr=inf;
		// cout<<s<<endl<<t<<endl<<S<<endl<<T<<endl;
		for(int i=0;i<n;i++) a[0][i]=s[i]-'0',a[1][i]=t[i]-'0';
		for(int i=0;i<n;i++) s1[0][i]=(i?s1[0][i-1]:0)+(s[i]=='1');
		for(int i=0;i<n;i++) s1[1][i]=(i?s1[1][i-1]:0)+(t[i]=='1');
		// cout<<"A";return 0;
		for(int i=0;i<n;i++) {
			if(S[i]=='0') {l[0][++sz[0]]=i,r[0][sz[0]]=i; continue;}
			rr=min(rr,i);
			if(i==n-1||S[i+1]=='0') l[0][++sz[0]]=rr,r[0][sz[0]]=i,rr=inf;
		}
		for(int i=0;i<n;i++) {
			if(T[i]=='0') {l[1][++sz[1]]=i,r[1][sz[1]]=i; continue;}
			rr=min(rr,i);
			if(i==n-1||T[i+1]=='0') l[1][++sz[1]]=rr,r[1][sz[1]]=i,rr=inf;
		}
		Solve();
		cout<<ans<<endl;
	}
	return 0;
}
/*
*/