#include <bits/stdc++.h>   using namespace std;   long long int max(long long int a, long long int b) {     if (a > b)       return a;     else       return b;   }   void solve() {     int n;     cin >> n;     vector<int> a(2 * n);     for (int i = 0; i < 2 * n; i++) {       cin >> a[i];     }     int din = 0;     for (int i = 0; i < 2 * n; i++) {       if (a[i] == 1)         din += 1;       else         din -= 1;     }     if (din == 0) {       cout << 0 << endl;       return;     }     map<int, int> m;     int dr = 0;     m[0] = n - 1;     for (int i = n; i < 2 * n; i++) {       if (a[i] == 1)         dr += 1;       else         dr -= 1;       if (!m.count(dr)) {         m[dr] = i;       }     }     int ans = 1e9 + 7;     int dl = 0;     if (m.count(din)) {       ans = min(ans, m[din] - n + 1);     }     for (int i = n - 1; i >= 0; i--) {       if (a[i] == 1)         dl += 1;       else         dl -= 1;       int q = din - dl;       if (m.count(q)) {         ans = min(ans, m[q] - i + 1);       }     }     cout << ans << endl;   }   int main() {     int t;     cin >> t;     while (t--) {       solve();     }   }   