#include <iostream>
#include <vector>

using namespace std;

const int kMaxN = 1e5 + 11;

int T, n, ans;
int ed[2];
pair<pair<int, int>, int> v1[kMaxN], v2[kMaxN];
pair<int, int> num;
string s[11];

int main() {
	freopen("edit.in", "r", stdin);
	freopen("edit.out", "w", stdout);
  ios::sync_with_stdio(0);
	cin.tie(0), cout.tie(0);
	cin >> T;
	while(T--) {
		cin >> n;
		for(int i = 0; i < 4; i++) {
			cin >> s[i];
		}
		for(int i = 0; i <= n; i++) {
			if(i < n && s[2][i] == '1') {
				num.first += (s[0][i] == '0');
				num.second += (s[0][i] == '1');
			} else {
				v1[ed[0]] = {num, i};
				ed[0]++;
				num = {0, 0};
			}
		}
		for(int i = 0; i <= n; i++) {
			if(i < n && s[3][i] == '1') {
				num.first += (s[1][i] == '0');
				num.second += (s[1][i] == '1');
			} else {
				v2[ed[1]] = {num, i};
				ed[1]++;
				num = {0, 0};
			}
		}
		for(int i = 0, j = 0; i < ed[0] && j < ed[1];) {
			// cout << ' ' << ans << '\n';
			if(v1[i].second == v2[j].second) {
				int tmp = v1[i].second;
				ans += min(v1[i].first.first, v2[j].first.first) + 
				min(v1[i].first.second, v2[j].first.second) + 
				(tmp < n && s[0][tmp] == s[1][tmp]);
				i++, j++;
			} else if(v1[i].second > v2[j].second) {
				int tmp = min(v1[i].first.first, v2[j].first.first);
				v1[i].first.first -= tmp;
				v2[j].first.first -= tmp;
				v1[i].first.second -= v2[j].first.first;
				ans += tmp;
				tmp = min(v1[i].first.second, v2[j].first.second);
				v1[i].first.second -= tmp;
				v2[j].first.second -= tmp;
				v1[i].first.first -= v2[j].first.second;
				ans += tmp;
				if(v2[j].second < n) {
					if(s[1][v2[j].second] == '0') {
						if(v1[i].first.first > 0) {
							v1[i].first.first--;
							ans++;
						} else {
							v1[i].first.second--;
						}
					}
					if(s[1][v2[j].second] == '1') {
						if(v1[i].first.second > 0) {
							v1[i].first.second--;
							ans++;
						} else {
							v1[i].first.first--;
						}
					}
				}
				j++;
			} else if(v1[i].second < v2[j].second) {
				int tmp = min(v1[i].first.first, v2[j].first.first);
				v1[i].first.first -= tmp;
				v2[j].first.first -= tmp;
				v2[j].first.second -= v1[i].first.first;
				ans += tmp;
				tmp = min(v1[i].first.second, v2[j].first.second);
				v1[i].first.second -= tmp;
				v2[j].first.second -= tmp;
				v2[j].first.first -= v1[i].first.second;
				ans += tmp;
				if(v1[i].second < n) {
					if(s[0][v1[i].second] == '0') {
						if(v2[j].first.first > 0) {
							v2[j].first.first--;
							ans++;
						} else {
							v2[j].first.second--;
						}
					}
					if(s[0][v1[i].second] == '1') {
						if(v2[j].first.second > 0) {
							v2[j].first.second--;
							ans++;
						} else {
							v2[j].first.first--;
						}
					}
				}
				i++;
			}
		}
		cout << ans << '\n';
		ans = 0;
		ed[0] = ed[1] = 0;
	}
	return 0;
}