func_code_string: #include <bits/stdc++.h>   const double eps = (1e-5);   using namespace std;   int dcmp(long double a, long double b) {     return fabsl(a - b) <= eps ? 0 : (a > b) ? 1 : -1;   }   long long getBit(long long num, int idx) { return ((num >> idx) & 1ll) == 1; }   int setBit1(int num, int idx) { return num | (1 << idx); }   long long setBit0(long long num, int idx) { return num & ~(1ll << idx); }   long long flipBit(long long num, int idx) { return num ^ (1ll << idx); }   void M() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);   }   int countNumBit1(int mask) {     int ret = 0;     while (mask) {       mask &= (mask - 1);       ++ret;     }     return ret;   }   int arr[3009], E[4500009];   int main() {     int n;     cin >> n;     for (int i = 0; i < n; i++) {       cin >> arr[i];     }     int cnt = 0;     while (1) {       int fl = 0;       for (int i = 0; i < n; i++) {         if (i + 1 < n && arr[i] > arr[i + 1])           swap(arr[i], arr[i + 1]), cnt++, fl = 1;       }       if (!fl) break;     }     E[1] = 1;     for (int i = 2; i <= cnt; i++) E[i] = 4 + E[i - 2];     cout << fixed << setprecision(9) << (double)E[cnt] << endl;   }   