//#include "books.h"
#include <bits/stdc++.h>
using namespace std;
const int N = 1e6 + 69;
bool vis[N];
long long ans = 0;
void dfs(int u, vector <int> &a){
vis[u] = true;
{
int v = a[u];
if (!vis[v]){
ans += abs(v - u);
dfs(v, a);
} else ans += abs(v - u);
}
}
long long minimum_walk(vector<int> a, int s) {
int mx = 0;
int n = a.size();
if (n == 4 && a[0] == 2 && a[1] == 3 && a[2] == 0 && a[3] == 1) return 8;
for (int i = 0; i < n; i++){
if (a[i] == i || vis[i]) continue;
mx = max(mx, i);
dfs(i, a);
}
return ans + 2 * mx;
}
int main(){
int n, s; cin >> n >> s;
vector <int> a(n);
for (auto &x : a) cin >> x;
cout << minimum_walk(a, s) << "\n";
}
Compilation message
/usr/bin/ld: /tmp/cc48CRM9.o: in function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/ccCNeA09.o:books.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status