#include<bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 50;
int cnts1_1[maxn], cnts1_0[maxn];
int cnts2_1[maxn], cnts2_0[maxn];
int s1_to[maxn];//the part every 01 belong to
int s2_to[maxn];
int T;
int n;
string s1, s2;
string t1, t2;
void cut() {
    int p = 1;
    for (int i = 0; i < n; i++) {
        int ok = 0;
        while (t1[i] == '0') {i++; ok = 1;}
        if (i == n) break;
        p += ok;
        if (s1[i] == '0') cnts1_0[p]++;//if there is no correct 01 point to, then it is 0
        if (s1[i] == '1') cnts1_1[p]++;
        s1_to[i] = p;
    }
    p = 1;
    for (int i = 0; i < n; i++) {
        int ok = 0;
        while (t2[i] == '0') {i++; ok = 1;}
        if (i == n) break;
        p += ok;
        if (s2[i] == '0') cnts2_0[p]++;//if there is no correct 01 point to, then it is 0
        if (s2[i] == '1') cnts2_1[p]++;
        s2_to[i] = p;
    }
}
int main() {
    freopen("edit.in", "r", stdin);
    freopen("edit.out", "w", stdout);
    scanf("%d", &T);
    while (T--) {
        int ans = 0;
        scanf("%d ", &n);
        cin>>s1>>s2;
        cin>>t1>>t2;
        memset(cnts1_0, 0, sizeof(cnts1_0));
        memset(cnts1_1, 0, sizeof(cnts1_1));
        memset(cnts2_0, 0, sizeof(cnts2_0));
        memset(cnts2_1, 0, sizeof(cnts2_1));
        memset(s1_to, 0, sizeof(s1_to));
        memset(s2_to, 0, sizeof(s2_to));
        cut();
        for (int i = 0; i < n; i++) {//discuss the limit place
            if (t1[i] == '0' && t2[i] == '0') {//case 1
                if (s1[i] == s2[i]) ans++;
            }
            else if (t1[i] == '1' && t2[i] == '0') {//case 2
                if (s2[i] == '1') {
                    if (cnts1_1[s1_to[i]] > 0) {
                        ans++;
                        cnts1_1[s1_to[i]]--;
                    }
                }
                else if (s2[i] == '0') {
                    if (cnts1_0[s1_to[i]] > 0) {
                        ans++;
                        cnts1_0[s1_to[i]]--;
                    }
                }
            }
            else if (t1[i] == '0' && t2[i] == '1') {
                if (s1[i] == '1') {
                    if (cnts2_1[s2_to[i]] > 0) {
                        ans++;
                        cnts2_1[s2_to[i]]--;
                    }
                }
                else if (s1[i] == '0') {
                    if (cnts2_0[s2_to[i]] > 0) {
                        ans++;
                        cnts2_0[s2_to[i]]--;
                    }
                }
            }
        }
        for (int i = 0; i < n; i++) {
            if (t1[i] == '0' || t2[i] == '0') continue;
            if (cnts1_0[s1_to[i]] > 0 && cnts2_0[s2_to[i]] > 0) {
                ans++;
                cnts1_0[s1_to[i]]--;
                cnts2_0[s2_to[i]]--;
            }
            else if (cnts1_1[s1_to[i]] > 0 && cnts2_1[s2_to[i]] > 0) {
                ans++;
                cnts1_1[s1_to[i]]--;
                cnts2_1[s2_to[i]]--;
            }
        }
        cout<<ans<<endl;
    }
    return 0;
}