#include "books.h"
#include <bits/stdc++.h>
using namespace std;
#define ll long long
int n;
long long minimum_walk(vector<int> p, int s) {
ll ans = 0;
n = p.size();
// s = 0
int lst = -1;
vector<int> idx(n, 0);
for (int i = 0; i < n; i++) idx[p[i]] = i;
int currPos = 0;
bool toL = true;
int carry = p[0];
idx[carry] = -1;
for (int i = 0; i < n; i++) {
if (toL) {
int goal = -1;
for (int i = n-1; i >= 0; i--) {
if (idx[i] != i) {
goal = i;
break;
}
}
if (goal == -1) return ans + currPos;
for (int i = currPos+1; i <= goal; i++) {
ans++;
if (p[i] > carry || i == carry) {
idx[carry] = i;
idx[p[i]] = -1;
swap(p[i], carry);
}
}
currPos = goal;
toL = false;
}
else {
int goal = -1;
for (int i = 0; i < n; i++) {
if (idx[i] != i) {
goal = i;
break;
}
}
if (goal == -1) return ans + currPos;
for (int i = currPos - 1; i >= goal; i--) {
ans++;
if (p[i] < carry) {
idx[carry] = i;
idx[p[i]] = -1;
swap(p[i], carry);
}
}
currPos = goal;
toL = true;
}
}
return ans + currPos;
}
