func_code_string: #include <bits/stdc++.h>   using namespace std;   const long long maxN = 1e7 + 5;   const long long inf = 1e10;   const long long mod = 1e9 + 7;   long long n;   long long a[maxN];   double f[maxN];   int main() {     ios_base::sync_with_stdio(0);     cin >> n;     for (long long i = 1; i <= n; i++) {       cin >> a[i];     }     long long cnt = 0;     for (long long i = 1; i <= n; i++) {       for (long long j = i + 1; j <= n; j++)         if (a[i] > a[j]) cnt++;     }     f[0] = 0.0;     f[1] = 1.0;     for (long long i = 2; i <= cnt + 2; i++) {       f[i] = f[i - 2] + 4.0;     }     printf( %.10f , f[cnt]);     return 0;   }   