#include "books.h" #include <bits/stdc++.h> using namespace std; using ll = long long; using vll = vector<ll>; using vi = vector<int>; using ii = pair<int, int>; struct UF { vi e; UF(int N) : e(N, -1) {} int repr(int u) { while(e[u] >= 0) u = e[u]; return u; } int join(int u, int v) { u = repr(u); v = repr(v); if(u == v) return 0; if(e[u] >= e[v]) swap(u, v); e[u] += e[v]; e[v] = u; return 1; } }; long long minimum_walk(vi p, int s) { int n = p.size(); vi on(n, 0), sum(n, 0); int mi = n, ma = 0; for(int i = 0; i < n; ++i) { int st = min(i, p[i]); int dr = max(i, p[i]); ++sum[st]; --sum[dr]; if(st != dr) { ma = max(ma, dr); mi = min(mi, st); } } for(int i = 1; i < n; ++i) sum[i] += sum[i - 1]; ll re = 0; for(int i = 0; i < n; ++i) re += abs(i - p[i]); for(int i = s - 1; i >= mi; --i) { if(!sum[i]) re += 2; } for(int i = s; i < ma; ++i) if(!sum[i]) re += 2; return re; }