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

#define real signed
#define enl '\n'
#define inl inline
#define tot_time cerr << 1.0 * clock() / CLOCKS_PER_SEC << 's' << enl;
#define tot_memory cerr << 1.0 * abs(&mst - &men) / 1024.0 / 1024.0 << "MB" << enl;
typedef long long int lli;
typedef pair<int, int> pii;
typedef pair<lli, lli> pll;

namespace IO {
    #define RS(filein, fileout) freopen(filein, "r", stdin), freopen(fileout, "w", stdout);
    #define TD std::ios::sync_with_stdio(false), std::cin.tie(NULL), std::cout.tie(NULL);
    #define getchar() ((tt == ss) && (tt = (ss = In) + fread(In, 1, 1 << 20, stdin), ss == tt) ? EOF : *ss++)
    #define putln putchar('\n')
    #define putsp putchar(' ')

    char In[1 << 20], *ss = In, *tt = In;

    inl lli read() {
        lli x = 0, f = 1; char ch = getchar();
        for (; ch < '0' || ch > '9'; ch = getchar()) if (ch == '-') f = -1;
        for (; ch >= '0' && ch <= '9'; ch = getchar()) x = ((x << 1) + (x << 3) + (ch ^ 48));
        return x * f;
    }

    inl void writ(lli x) {
        if (x < 0) {putchar('-'); x = -x; }
        if (x >= 10) writ(x / 10);
        return putchar(x % 10 + '0'), void();
    }

};
using namespace IO;

namespace Modulo {
    const int mod = 1000000007;
    #define adwm(x, w) (((x += w) >= mod) && (x -= mod))
    #define suwm(x, w) (((x -= w) < 0) && x += mod))
};
using namespace Modulo;

const double pi = 3.14159265359879323846;
const uint64_t Ba = 1313131;
const uint64_t Bb = 233333;
const uint64_t Ma = 998244353;
const uint64_t Mb = 1000000007;
mt19937_64 mrn(std::chrono::system_clock::now().time_since_epoch().count());

bool mst;
int n;
string s, t;
string ls, lt;
bool men;

void init() {
    return void();
}

void solv() {
    cin >> n;
    cin >> s >> t;
    cin >> ls >> lt;
    s = ' ' + s, t = ' ' + t;
    ls = ' ' + ls, lt = ' ' + lt;
    s = s + '&', t = t + '*';
    ls = ls + '0', lt = lt + '0';
    int an = 0;
    int cs1 = 0, cs0 = 0, ct1 = 0, ct0 = 0;
    int is = 1, it = 1;
    for (; is <= n || it <= n; ) {
        for (; is <= n && ls[is] != '0'; is++) cs0 += s[is] == '0', cs1 += s[is] == '1';
        for (; it <= n && lt[it] != '0'; it++) ct0 += t[it] == '0', ct1 += t[it] == '1';
        int d0 = min(cs0, ct0), d1 = min(cs1, ct1);
        an += d0 + d1;
        cs0 -= d0, ct0 -= d0, cs1 -= d1, ct1 -= d1;
        if (is > it) {
            if (ct0) cs1 -= ct0, ct0 = 0;
            if (ct1) cs0 -= ct1, ct1 = 0;
            if (t[it] == '1') {
                if (cs1) cs1--, an++;
                else cs0--;
            }
            else {
                if (cs0) cs0--, an++;
                else cs1--;
            }
            it++;
        }
        else if (it > is) {
            if (cs0) ct1 -= cs0, cs0 = 0;
            if (cs1) ct0 -= cs1, cs1 = 0;
            if (s[is] == '1') {
                if (ct1) ct1--, an++;
                else ct0--;
            }
            else {
                if (ct0) ct0--, an++;
                else ct1--;
            }
            is++;
        }
        else an += s[is] == t[it], is++, it++, cs0 = cs1 = ct0 = ct1 = 0;
    }
    cout << an << enl;
    return void();
}

#define Silf
#define Chpa
#define Clsy
real main() {
#ifdef Silf
    RS("edit.in", "edit.out")
#endif
#ifdef Chpa
    tot_memory
#endif
#ifdef Clsy
    TD
#endif
    int ques = 1;
    cin >> ques;
    for (; ques--; ) solv();
#ifdef Chpa
    tot_time
#endif
    return 0;
}