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

vector<int> locks(string s) {
    vector<int> ret;
    int n = s.size();
    for (int i = 0; i < n; i++)
        if (s[i] == '0') ret.push_back(i);
    return ret;
}

vector<int> fore(string s) {
    vector<int> a, pre;
    for (char &c : s) a.push_back(c - '0');
    partial_sum(a.begin(), a.end(), back_inserter(pre));
    pre.insert(pre.begin(), 0);
    return pre;
}

void solve() {
    int n;
    cin >> n;
    string s1, s2, t1, t2;
    cin >> s1 >> s2 >> t1 >> t2;
    vector<int> lc1 = locks(t1), lc2 = locks(t2);
    lc1.push_back(n), lc2.push_back(n);
    vector<int> p1 = fore(s1), p2 = fore(s2);
    int ans = 0, rm1[2], rm2[2];
    rm1[1] = p1[lc1[0]], rm2[1] = p2[lc2[0]], rm1[0] = lc1[0] - rm1[1], rm2[0] = lc2[0] - rm2[1];
    for (int l = 0; l < n; ) {
        int nl1 = *upper_bound(lc1.begin(), lc1.end(), l);
        int nl2 = *upper_bound(lc2.begin(), lc2.end(), l);

        if (t1[l] == '0' && t2[l] == '0') {
            ans += (s1[l] == s2[l]), l++;
            rm1[1] = p1[nl1] - p1[l], rm1[0] = nl1 - l - rm1[1];
            rm2[1] = p2[nl2] - p2[l], rm2[0] = nl2 - l - rm2[1];
        } else if (t1[l] == '0') {
            if (rm2[s1[l] - '0'] > 0)
                rm2[s1[l] - '0']--, l++, rm1[1] = p1[nl1] - p1[l], rm1[0] = nl1 - l - rm1[1], ans++;
            else
                rm2[!(s1[l] - '0')]--, l++, rm1[1] = p1[nl1] - p1[l], rm1[0] = nl1 - l - rm1[1];
        } else if (t2[l] == '0') {
            if (rm1[s2[l] - '0'] > 0)
                rm1[s2[l] - '0']--, l++, rm2[1] = p2[nl2] - p2[l], rm2[0] = nl2 - l - rm2[1], ans++;
            else
                rm1[!(s2[l] - '0')]--, l++, rm2[1] = p2[nl2] - p2[l], rm2[0] = nl2 - l - rm2[1];
        } else {
            int M0 = min(rm1[0], rm2[0]), M1 = min(rm1[1], rm2[1]), D = min(nl1, nl2) - l - M0 - M1;
            rm1[0] -= M0, rm2[0] -= M0, rm1[1] -= M1, rm2[1] -= M1;
            if (nl1 < nl2) {
                rm1[0] = rm1[1] = 0;
                if (rm2[0] == 0) rm2[1] -= D; else rm2[0] -= D;
            } else {
                rm2[0] = rm2[1] = 0;
                if (rm1[0] == 0) rm1[1] -= D; else rm1[0] -= D;
            }
            ans += M0 + M1, l = min(nl1, nl2);
        }
    }
    cout << ans << endl;
}

int main() {
    freopen("edit.in", "r", stdin);
    freopen("edit.out", "w", stdout);
    int T;
    cin >> T;
    while (T--) solve();
}