#include "books.h"
#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define For(i, l, r) for (auto i = (l); i < (r); i++)
#define ForE(i, l, r) for (auto i = (l); i <= (r); i++)
#define FordE(i, l, r) for (auto i = (l); i >= (r); i--)
#define bend(a) (a).begin(), (a).end()
#define isz(a) ((signed)a.size())
using ll = long long;
const int N = 1e6 + 5;
int n, s;
int a[N];
bool vis[N];
int cnt_edge[N];
ll pref_cnt_edge[N];
ll ans;
ll minimum_walk(vector <int> _a, int _s){
n = isz(_a);
s = _s;
For(i, 0, n){
a[i] = _a[i];
}
For(i, 0, n){
if (vis[i]){
continue;
}
ll tans = 0;
int l = i, r = i;
{
int u = i;
do{
vis[u] = true;
l = min(l, u);
r = max(r, u);
int v = a[u];
tans += abs(u - v);
u = v;
} while (u != i);
}
ans += tans;
cnt_edge[l]++;
cnt_edge[r]--;
}
For(i, 1, n){
cnt_edge[i] += cnt_edge[i - 1];
}
For(i, 0, n){
pref_cnt_edge[i] = (i != 0 ? pref_cnt_edge[i - 1] : 0ll) + cnt_edge[i];
}
For(i, 0, n - 1){
if (cnt_edge[i] == 0 and pref_cnt_edge[n - 1] - (i != 0 ? pref_cnt_edge[i - 1] : 0ll) != 0){
ans += 2;
}
}
return ans;
}
