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

const int N = 2e5 + 10;
int n, T, ans;
char h1[N], h2[N], h3[N], h4[N];
char *a = h1, *b = h2, *s = h3, *t = h4;

void add(int &p, int &x, int &y, char * o)
{
  p++;
  if (p > n) return;
  x += (o[p] == '0');
  y += (o[p] == '1');
}

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 >> a + 1 >> b + 1 >> s + 1 >> t + 1;
    ans = 0;
    int p = 0, q = 0, cnt0 = 0, cnt1 = 0, cnt2 = 0, cnt3 = 0;
    while (!p || (s[p] != '0' && s[p + 1] != '0' && p < n)) add(p, cnt0, cnt1, a);
    while (!q || (t[q] != '0' && t[q + 1] != '0' && q < n)) add(q, cnt2, cnt3, b);
    while (p <= n) {
      // cerr << cnt0 << ' ' << cnt1 << ' ' << cnt2 << ' ' << cnt3 << ' ' << ans << endl;
      ans += min(cnt0, cnt2) + min(cnt1, cnt3);
      if (q < p) swap(a, b), swap(s, t), swap(cnt0, cnt2), swap(cnt1, cnt3), swap(p, q);
      cnt2 = max(0, min(cnt2 - cnt0, q - p));
      cnt3 = max(0, min(cnt3 - cnt1, q - p));
      cnt0 = cnt1 = 0;
      if (p == q) add(q, cnt2, cnt3, b);
      add(p, cnt0, cnt1, a);
      while (s[p] != '0' && s[p + 1] != '0' && p < n) add(p, cnt0, cnt1, a);
      while (t[q] != '0' && t[q + 1] != '0' && q < n) add(q, cnt2, cnt3, b);
    }
    cout << ans << endl;
  }
  return 0;
}