#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using V = vector<ll>;
using VV = vector<V>;
using P = pair<ll,ll>;
using M = map<ll,ll>;
using Q = queue<ll>;
using PQ = priority_queue<ll>;
using PQG = priority_queue<ll,V,greater<ll>>;
using S = set<ll>;
const ll MOD = 1000000007;
const ll Mod = 998244353;
const ll INF = 1LL << 60;
#define rep(i,n) for(int i = 0; i < n; i++)
#define rep2(i,s,n) for(int i = s; i < n; i++)
#define all(x) (x).begin(),(x).end()
template <class T>bool chmin(T &a, const T &b){if(a>b){a=b;return 1;}return 0;}
template <class T>bool chmax(T &a, const T &b){if(a<b){a=b;return 1;}return 0;}

int main() {
  int n;
  cin >> n;
  V p(n);
  rep(i,n){
    int a;
    cin >> a;
    p[a-1] = i+1;
  }
  ll ans = 0, anss = -p[0];
  rep(i,n-1){
    anss += p[i]*2 - p[i+1];
    chmax(ans, anss);
  }
  cout << ans << endl;
}