#include <bits/stdc++.h>
using namespace std;

void ALERT() {
    cout << "\tALERT!" << endl;
}

void solve() {
    int n;
    cin >> n;
    string s1, s2, t1, t2;
    cin >> s1 >> s2 >> t1 >> t2;
    bool l1[n], l2[n], b1[n], b2[n];
    for(int i = 0; i < n; i++) {
        l1[i] = (s1.at(i) == '1');
        l2[i] = (s2.at(i) == '1');
        b1[i] = (t1.at(i) == '1');
        b2[i] = (t2.at(i) == '1');
    }

    // lian xu hua bu ke geng gai qu jian
    if(!b1[1])          b1[0] = 0;
    if(!b1[n - 2])      b1[n - 1] = 0;
    if(!b2[1])          b2[0] = 0;
    if(!b2[n - 2])      b2[n - 1] = 0;
    for(int i = 1; i < n - 1; i++) {
        if(b1[i] && !b1[i - 1] && !b1[i + 1]) {
            b1[i] = 0;
        }
        if(b2[i] && !b2[i - 1] && !b2[i + 1]) {
            b2[i] = 0;
        }
    }

    int ans = 0;

    for(int i = 0; i < n; i++) {
        if(!b1[i] && !b2[i] && l1[i] == l2[i]) {
            ans++;
        }
    }

    vector<pair<int, int>> qj1, qj2;
    qj1.push_back(pair<int, int>(0, 0));
    qj2.push_back(pair<int, int>(0, 0));
    int s = 0, e = 0;
    while(s < n) {
        if(b1[s])   {
            for(e = s + 1; b1[e] && e < n; e++);
            qj1.push_back(pair<int, int>(s, e));
            s = e + 1;
        } else {
            s++;
            continue;
        }
    }
    s = 0, e = 0;
    while(s < n) {
        if(b2[s]) {
            for(e = s + 1; b2[e] && e < n; e++);
            qj2.push_back(pair<int, int>(s, e));
            s = e + 1;
        } else {
            s++;
            continue;
        }
    }
    qj1.push_back(pair<int, int>(n, n));
    qj2.push_back(pair<int, int>(n, n));

    int info1[n][2];   // from, to, count of 0 or count of 1, count;
    memset(info1, 0, sizeof(info1));
    for(int i = 0; i < qj1.size(); i++) {
        for(int j = qj1[i].first; j < qj1[i].second; j++) {
            if(l1[j])   info1[i][1]++;
            else        info1[i][0]++;
        }
    }
    int info2[n][2];   // from, to, count of 0 or count of 1, count;
    memset(info2, 0, sizeof(info2));
    for(int i = 0; i < qj2.size(); i++) {
        for(int j = qj2[i].first; j < qj2[i].second; j++) {
            if(l2[j])   info2[i][1]++;
            else        info2[i][0]++;
        }
    }

    for(int i = 1; i < qj1.size() - 1; i++) {
        for(int j = 0; j < qj2.size() - 1; j++) {
            pair<int, int> lockRange(qj2[j].second, qj2[j + 1].first);
            if(lockRange.second <= qj1[i].first)    continue;
            if(lockRange.first >= qj1[i].second)    break;
            int f = max(qj1[i].first, lockRange.first), t = min(qj1[i].second, lockRange.second);
            int co1 = 0, co0 = 0;
            for(int i = f; i < t; i++) {
                if(l2[i] == 1)  co1++;
                else            co0++;
            }

            ans += min(info1[i][0], co0) + min(info1[i][1], co1);
            info1[i][1] -= min(info1[i][1], co1);
            info1[i][0] -= min(info1[i][0], co0);
        }
    }
    for(int i = 1; i < qj2.size() - 1; i++) {
        for(int j = 0; j < qj1.size() - 1; j++) {
            pair<int, int> lockRange(qj1[j].second, qj1[j + 1].first);
            if(lockRange.second <= qj2[i].first)    continue;
            if(lockRange.first >= qj2[i].second)    break;
            int f = max(qj2[i].first, lockRange.first), t = min(qj2[i].second, lockRange.second);
            int co1 = 0, co0 = 0;
            for(int i = f; i < t; i++) {
                if(l1[i] == 1)  co1++;
                else            co0++;
            }

            ans += min(info2[i][0], co0) + min(info2[i][1], co1);
            info2[i][1] -= min(info2[i][1], co1);
            info2[i][0] -= min(info2[i][0], co0);
        }
    }

    for(int i = 1; i < qj1.size() - 1; i++) {
        for(int j = 1; j < qj2.size() - 1; j++) {
            if(qj2[j].second <= qj1[i].first)   continue;
            if(qj2[j].first >= qj1[i].second)   break;

            int f = max(qj1[i].first, qj2[j].first);
            int t = min(qj1[i].second, qj2[j].second);
            int cha = t - f;
            int co1 = min(info1[i][1], info2[j][1]);
            int co0 = min(info1[i][0], info2[j][0]);

            int temp = min(cha, co0);
            ans += temp;
            cha -= temp;
            info1[i][0] -= temp;
            info2[j][0] -= temp;

            temp = min(cha, co1);
            ans += temp;
            cha -= temp;
            info1[i][1] -= temp;
            info2[j][1] -= temp;
        }
    }

    cout << ans << endl;

}

int main() {
    freopen("edit.in", "r", stdin);
    freopen("edit.out", "w", stdout);

    int t;
    cin >> t;
    for(int i = 0; i < t; i++) {
        solve();
    }
}