func_code_string: #include <bits/stdc++.h>   using namespace std;   long long po(long long a, long long x, long long m) {     if (x == 0) {       return 1;     }     long long ans = 1;     long long k = 1;     while (k <= x) {       if (x & k) {         ans = ((ans * a) % m);       }       k <<= 1;       a *= a;       a %= m;     }     return ans;   }   int32_t main() {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     cout.tie(NULL);     long long t;     cin >> t;     while (t--) {       long long n;       cin >> n;       string a, b;       cin >> a >> b;       bool f[n + 1][2];       for (long long i = 0; i < n; i++) {         if (a[i] ==  1  || a[i] ==  2 )           f[i][0] = false;         else           f[i][0] = true;         if (b[i] ==  1  || b[i] ==  2 )           f[i][1] = false;         else           f[i][1] = true;       }       long long bll = 0;       bool flag = true;       bool k = false;       for (long long i = 0; i < n; i++) {         if (i != n && !f[i][bll]) {           continue;         }         if (i != n && (f[i][0] && !f[i][1]) || (f[i][1] && !f[i][0])) {           flag = false;           break;         }         bll ^= 1;       }       if (flag && bll == 1)         cout <<  YES               <<   n ;       else         cout <<  NO               <<   n ;     }     return 0;   }   