#include "books.h"
#include <math.h>
#include <algorithm>
long long minimum_walk(std::vector<int> p, int s) {
int n = p.size();
long long dist = 0, ans = 0;
int greatest = s, l = s, r = s;
for (int i = s; ~i; i--) {
if (p[i] != i) {
ans += abs(p[i] - i);
if (p[i] > s) {
l = std::min(l, i);
r = std::max(r, p[i]);
}
if (i < greatest) dist += i - greatest;
greatest = std::min(greatest, std::min(i, p[i]));
}
}
greatest = s;
for (int i = s + 1; i < n; i++) {
if (p[i] != i) {
ans += abs(p[i] - i);
if (p[i] < s) {
l = std::min(l, p[i]);
r = std::max(r, p[i]);
}
if (i > greatest) dist += i - greatest;
greatest = std::max(greatest, std::max(i, p[i]));
}
}
return ans + 2 * dist + std::min(s - l, r - s);
}
