// #include <bits/stdc++.h> #include <iostream> #include <cmath> #include <algorithm> #include <map> #include <unordered_map> #include <vector> #include <iomanip> #include <string> #include <queue> #include <set> #include <deque> using namespace std; #define int long long #define endl "\n" #define fi first #define se second const int M=1e9+7; const int inf = 1e14; const int LOG=17; const int N=2e5+5; int n , m , c , w , k , t=1 , q=1 , x , y , z , l , r; int fn[N]; void up(int i,int x){ if (i<N){ fn[i]+=x; up(i+(i&-i),x); } } int pr(int i){ if (i==0)return 0; return fn[i]+pr(i-(i&-i)); } void solve(){ cin >> n; vector<int>a(1<<n); for (int i=0;i<(1<<n);i++){ cin >> x; a[x]=i; } for (int j=0;j<n;j++){ int c1=0,c2=0; int d=0; for (int i=0;i<(1<<n);i++){ if (a[i]&(1<<j)){ d++; } else{ c1+=d; } a[i]^=(1<<j); } d=0; for (int i=0;i<(1<<n);i++){ if (a[i]&(1<<j)){ d++; } else{ c2+=d; } } if (c1<c2){ for (int i=0;i<(1<<n);i++){ a[i]^=(1<<j); } } } vector<int>l(n); for (int j=0;j<n;j++){ int c=0; for (int i=0;i<=(1<<n);i++){ fn[i]=0; } for (int i=0;i<(1<<n);i++){ c+=i-pr(a[i]); up(a[i]+1,1); } l[j]=c; for (int i=0;i<(1<<n);i++){ int u=(a[i]&(1<<(n-1))); a[i]-=u; a[i]*=2; a[i]+=(u==(1<<(n-1))); } } int in=0; for (int i=1;i<n;i++){ if (l[i]<l[in]){ in=i; } } for (int j=0;j<in;j++){ for (int i=0;i<(1<<n);i++){ int u=(a[i]&(1<<(n-1))); a[i]-=u; a[i]*=2; a[i]+=(u==(1<<(n-1))); } } int c=0; for (int i=0;i<=(1<<n);i++){ fn[i]=0; } for (int i=0;i<(1<<n);i++){ c+=i-pr(a[i]); up(a[i]+1,1); } cout << c << endl; // for (int i:a){ // cout << i << " "; // } // cout << endl; cout << 1 << endl; } signed main() { // #ifndef ONLINE_JUDGE // freopen("input.txt","r" ,stdin); // freopen("output.txt","w",stdout); // #endif ios::sync_with_stdio(0);//DO NOT USE IN INTERACTIVE cin.tie(0), cout.tie(0);//DO NOT USE IN INTERACTIVE cout << fixed << setprecision(9); srand(time(0)); // int t=1; // cin >> t; for (int _=1;_<=t;_++){ solve(); q++; } }