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#include<bits/stdc++.h>
using namespace std;
typedef unsigned long long ull;
typedef long long ll;

const int N = 1e5+5;

bool s0[N], s1[N], t0[N], t1[N];
int T, n;

char inp[N];

int l = 1, r0 = 1, r1 = 1, cnt0[2], cnt1[2];
inline void solve()
{
	ll ans = 0;
	while(1) {
		if(r0 > n+1 && r1 > n+1) break;
		while(t0[r0] && r0<=n)
		{
			cnt0[s0[r0]]++;
			r0++;
		}
		while(t1[r1] && r1<=n)
		{
			cnt1[s1[r1]]++;
			r1++;
		}
//		printf("try[%d, %d][%d, %d]cnt0(%d, %d), cnt1(%d, %d)%d -> ", l, r0, l, r1, cnt0[0], cnt0[1], cnt1[0], cnt1[1], ans);
		if(r0 == r1)//A/B
		{
			ans += min(cnt0[0], cnt1[0])+min(cnt0[1], cnt1[1]);
			ans += (s0[r0]==s1[r1]);
//			printf("%d cnt0(%d, %d), cnt1(%d, %d)\n", ans, cnt0[0], cnt0[1], cnt1[0], cnt1[1]);
			l = r0+1; r0++; r1++;
			cnt0[0] = cnt1[0] = cnt0[1] = cnt1[1] = 0;
//			printf("%d cnt0(%d, %d), cnt1/(%d, %d)\n", ans, cnt0[0], cnt0[1], cnt1[0], cnt1[1]);
			continue;
		}
		if(r0 < r1) {
//			printf("tag1:cnt0(%d, %d), cnt1(%d, %d)\n", cnt0[0], cnt0[1], cnt1[0], cnt1[1]);
			if(cnt0[0]<=cnt1[0]) {
				ans += cnt0[0]; cnt1[0]-=cnt0[0]; cnt0[0] = 0; 
//				printf("tag2:cnt0(%d, %d), cnt1(%d, %d)\n", cnt0[0], cnt0[1], cnt1[0], cnt1[1]);
				if(cnt0[1]<=cnt1[1]) {
					ans += cnt0[1]; cnt1[1]-=cnt0[1]; cnt0[1] = 0; 
				}
				else {
					ans+=cnt1[1];
					cnt0[1]-=cnt1[1]; cnt1[1] = 0;
					cnt1[0]-=cnt0[1];
					cnt0[1] = 0; 
				}
//				printf("tag3:cnt0(%d, %d), cnt1(%d, %d)\n", cnt0[0], cnt0[1], cnt1[0], cnt1[1]);
			}
			else {
				ans+=cnt1[0];
				cnt0[0]-=cnt1[0]; cnt1[0] = 0;
				cnt1[1]-=cnt0[0];
				cnt0[0] = 0;
				if(cnt0[1]<=cnt1[1]) {
					ans += cnt0[1]; cnt1[1]-=cnt0[1]; cnt0[1] = 0;
				}
				else {
					ans+=cnt1[1];
					cnt0[1]-=cnt1[1]; cnt1[1] = 0;
					cnt1[0]-=cnt0[1];
					cnt0[1] = 0; 
				}
			}
			if(cnt1[s0[r0]])
			{
//				printf("checks0r0:%d\n", s0[r0]);
				cnt1[s0[r0]]--; ans++;
			} 
			else
			{
//				printf("checks0r0:%d\n", s0[r0]); 
				cnt1[!s0[r0]]--;
			}
			l = r0+1, r0 = r0+1;
//			printf("%d cnt0(%d, %d), cnt1/(%d, %d)\n", ans, cnt0[0], cnt0[1], cnt1[0], cnt1[1]);
			continue;
		}
		if(r0 > r1) {
//			printf("tag4:cnt0(%d, %d), cnt1(%d, %d)\n", cnt0[0], cnt0[1], cnt1[0], cnt1[1]);
			if(cnt1[0]<=cnt0[0]) {
				ans += cnt1[0]; cnt0[0]-=cnt1[0]; cnt1[0] = 0; 
//				printf("tag5:cnt0(%d, %d)/, cnt1(%d, %d)\n", cnt0[0], cnt0[1], cnt1[0], cnt1[1]);
				if(cnt1[1]<=cnt0[1]) {
					ans += cnt1[1]; cnt0[1]-=cnt1[1]; cnt1[1] = 0;
				}
				else { 
					ans+=cnt0[1];
					cnt1[1]-=cnt0[1]; cnt0[1] = 0;
					cnt0[0]-=cnt1[1];
					cnt1[1] = 0; 
				}
//				printf("tag6:cnt0(%d, %d), cnt1(%d, %d)\n", cnt0[0], cnt0[1], cnt1[0], cnt1[1]);
			}
			else {
				ans+=cnt0[0]; 
				cnt1[0]-=cnt0[0]; cnt0[0] = 0;
				cnt0[1]-=cnt1[0];
				cnt1[0] = 0;
				if(cnt1[1]<=cnt0[1]) {
					ans += cnt1[1]; cnt0[1]-=cnt1[1]; cnt1[1] = 0; 
				}
				else {
					ans+=cnt0[1];
					cnt1[1]-=cnt0[1]; cnt0[1] = 0;
					cnt0[0]-=cnt1[1];
					cnt1[1]=0; 
				}
			}
			if(cnt0[s1[r1]])
			{
				cnt0[s1[r1]]--; ans++;
			} 
			else
			{
				cnt0[!s1[r1]]--;
			}
			l = r1+1, r1 = r1+1;
			
//			printf("%d cnt0(%d, %d), cnt1(%d, %d)\n", ans, cnt0[0], cnt0[1], cnt1[0], cnt1[1]);
		}
	}
	printf("%lld\n", ans);
}
inline void clear()
{
	l = 1, r0 = 1, r1 = 1, cnt0[1]=cnt0[0] = cnt1[0] = cnt1[1] = 0;
}

inline void solveA()
{
	ll ans = 0;
	for(int i = 1; i <= n; i++) {
		if(s1[i] == s0[1]) ans++;
	}
	printf("%lld\n", ans);
}
inline void solveB()
{
	int ans = 0;
	while(1) {
		if(r0 > n || r1 > n) break;
		while(t0[r0] && r0<=n)
		{
			cnt0[s0[r0]]++;
			r0++;
		}
		while(t1[r1]&&r1<=n)
		{
			cnt1[s1[r1]]++;
			r1++;
		}
		if(r0 == r1)//A/B
		{
			ans += min(cnt0[0], cnt1[0])+min(cnt0[1], cnt1[1]);
			ans += (s0[r0]==s1[r1]);
			l = r0; r0++; r1++;
			cnt0[0] = cnt1[0] = cnt0[1] = cnt1[1] = 0;
			continue;
		}
	}
	printf("%d\n", ans);
}

int main()
{
	freopen("edit.in", "r", stdin);
	freopen("edit.out", "w", stdout);
	scanf("%d", &T);
	for(int test = 0; test < T; test++) {
		scanf("%d%s", &n, inp);
		for(int i = 1; i <= n; i++) {
			s0[i] = inp[i-1]-'0';
		}
		scanf("%s", inp);
		for(int i = 1; i <= n; i++) {
			s1[i] = inp[i-1]-'0';
		}
		scanf("%s", inp);
		for(int i = 1; i <= n; i++) {
			t0[i] = inp[i-1]-'0';
		}
		scanf("%s", inp);
		for(int i = 1; i <= n; i++) {
			t1[i] = inp[i-1]-'0';
		}
		t0[n+1] = 0;
		t1[n+1] = 0;
		s0[n+1] = 1;
		s1[n+1] = 0;
		bool flagA = true;
		for(int i = 1; i <= n; i++) {
			if(s0[i] != s0[1]) {
				flagA = false;
				break;
			}
		}
		bool flagB = true;
		for(int i = 1; i <= n; i++) {
			if(t0[i] != t1[i]) {
				flagB = false;
				break;
			}
		}
		if(!flagA)
		{
			if(flagB)
			{
				solveB();
			}
			else {
				solve();
			}
		}
		else {
			solveA();
		}
		clear();
//		printf("aaaa\n\n\n\n\n\n");
	}



	return 0;
}