func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     ios::sync_with_stdio(false);     int n;     cin >> n;     int a[2 * n], ans = 0;     for (int i = 0; i <= 2 * n - 1; i++) cin >> a[i];     for (int i = 0; i < 2 * n; i += 2) {       int j = i + 1;       while (a[j] != a[i]) j++;       ans += j - i - 1;       for (int k = j; k >= i + 2; k--) a[k] = a[k - 1];     }     cout << ans;     return 0;   }   