#include <bits/stdc++.h>
#define int long long
#define INF 0x3f3f3f3f3f3f3f3f
#define endl '\n'
using namespace std;
typedef pair<int, int> pii;
const int N = + 29;

int n, m;
string s1, s2, t1, t2;

bool judge1() {
	char ju = s1[0];
	for (auto i : s1)
		if (ju != i) return false;
	return true;
}

void sp1() {
	char ju = s1[0];
	int ans = 0;
	for (auto i : s2) {
		if (i == ju) ans++;
	}
	cout << ans << endl;
	return;
}

void sp2() {
	int ans = 0;
	int cnt10 = 0, cnt11 = 0, cnt20 = 0, cnt21 = 0;
	for (int i = 0; i < n; i++) {
		if (t1[i] == '0') {
			ans = ans + min(cnt10, cnt20) + min(cnt11, cnt21);
			cnt10 = 0, cnt11 = 0, cnt20 = 0, cnt21 = 0;
			if (s1[i] == s2[i]) ans++;
			continue;
		}
		if (s1[i] == '0') cnt10++;
		if (s1[i] == '1') cnt11++;
		if (s2[i] == '0') cnt20++;
		if (s2[i] == '1') cnt21++;
	}
	ans += min(cnt10, cnt20) + min(cnt11, cnt21);
	cout << ans << endl;
	return;
}

void tbcsolve() {
	cin >> n >> s1 >> s2 >> t1 >> t2;
	if (judge1()) {
		sp1();	
		return;
	}
	if (t1 == t2) {
		sp2();
		return;
	}
	int i = 0, j = 0, ans = 0;
	int cnt10 = 0, cnt11 = 0, cnt20 = 0, cnt21 = 0;
	char tt1, tt2;
	while (true) {
		for ( ; i < n; i++) {
			if (t1[i] == '0') {
				tt1 = s1[i];
				break;
			}
			if (s1[i] == '0') cnt10++;
			if (s1[i] == '1') cnt11++;
		}
		for ( ; j < n; j++) {
			if (t2[j] == '0') {
				tt2 = s2[j];
				break;
			}
			if (s2[j] == '0') cnt20++;
			if (s2[j] == '1') cnt21++;
		}
		
		if (i > j) {
			if (tt2 == '0') cnt20++;
			else cnt21++;
			
			if (cnt10 >= cnt20) {
				ans += cnt20;
				cnt10 -= cnt20;
			}
			else {
				ans += cnt10;
				cnt11 -= (cnt20 - cnt10);
				cnt10 = 0;
			}
			
			if (cnt11 >= cnt21) {
				ans += cnt21;
				cnt11 -= cnt21;
			}
			else {
				ans += cnt11;
				cnt10 -= (cnt21 - cnt11);
				cnt11 = 0;
			}
			cnt20 = cnt21 = 0;
			j++;
		}
		else if (i < j) {
			if (tt1 == '0') cnt10++;
			else cnt11++;
		
			if (cnt10 <= cnt20) {
				ans += cnt10;
				cnt20 -= cnt10;
			}
			else {
				ans += cnt20;
				cnt21 -= (cnt10 - cnt20);
				cnt20 = 0;
			}
			
			if (cnt11 <= cnt21) {
				ans += cnt11;
				cnt21 -= cnt11;
			}
			else {
				ans += cnt21;
				cnt20 -= (cnt11 - cnt21);
				cnt21 = 0;
			}
			
			cnt10 = cnt11 = 0;
			i++;
		}
		else {
			ans += min(cnt10, cnt20);
			ans += min(cnt11, cnt21);
			if (i < n && tt1 == tt2) ans++;
			cnt10 = cnt11 = cnt20 = cnt21 = 0;
			i++; j++;
		}
		if (i >= n && j >= n) break;
	} 
	
	cout << ans << endl;
}

void tbcinit() {

}

signed main() {
	freopen("edit.in", "r", stdin);
	freopen("edit.out", "w", stdout);
	ios:: sync_with_stdio(0), cin.tie(0), cout.tie(0);
	int zs = 1;
	cin >> zs;
	while (zs--) {
		tbcinit();
		tbcsolve();
	}
	return 0;
}
/*
1
10
0110111100
1111111100
1110000100
0110111011
*/