#include "books.h"
#include<bits/stdc++.h>
using namespace std;
#define mp make_pair
#define INF 10000000
#define MOD 1000000007
#define MID ((l+r)/2)
#define HASHMOD 2305843009213693951
#define ll long long
#define ull unsigned long long
#define F first
#define S second
typedef pair<ll, ll> ii;
typedef pair<ii, int> iii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef map<int, int> mii;
#define EPS 1e-6
#define FOR(i,n) for(int i=0;i<((int)(n));i++)
#define FORi(i,a,b) for(int i=((int)(a));i<((int)(b));i++)
#define FOA(v, a) for(auto v : a)
#define len(x) ((int)x.size())
int t, n;
vi a, b;
int s;
vi p;
vector<int> adj;
long long minimum_walk(std::vector<int> pp, int ss) {
s = ss;
p = pp;
int n = pp.size();
ll ans=0;
adj.resize(n);
vi v(n, 0);
FOR(i,n){
adj[i] = (p[i]);
ans+=abs(i-adj[i]);
v[min(i, adj[i])]++;
v[max(i, adj[i])]--;
}
FORi(i,1,n-1) v[i]+=v[i-1];
int last=n-1;
while(last>=0 && adj[last]==last) last--;
FORi(i,0,last+1){
//cout<<v[i]<<" ";
if(v[i]==0) ans+=2;
}
return ans;
}
