#include "books.h"
#include <bits/stdc++.h>
#define x first
#define y second
#define pb push_back
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pii;
const ll MAXN = 1e6 + 10;
vector<pii> pi;
bool vis[MAXN];
ll n;
ll ans;
bool done[MAXN];
ll nr[MAXN], nl[MAXN];
long long minimum_walk(std::vector<int> p, int s) {
for(int i=0; i<n; i++) ans += abs(cu - p[cu]);
n = p.size();
for(int i=0; i<n; i++){
if(!vis[i]){
ll cl = i, cr = i;
ll cu = i;
while(!vis[cu]){
cl = min(cu, cl);
cr = max(cu, cr);
vis[cu] = 1;
cu = p[cu];
}
pi.pb({cl, cr});
}
}
for(int i=0; i<n; i++) nr[i] = nl[i] = -1;
ll lar = s, fil = s;
ll cl = s, cr = s;
for(int i=0; i<pi.size(); i++){
if(pi[i].x <= s && s <= pi[i].y){
cl = min(cl, pi[i].x);
cr = max(cr, pi[i].y);
}
nr[pi[i].x] = pi[i].y;
nl[pi[i].y] = pi[i].x;
if(pi[i].x != pi[i].y){
lar = max(lar, pi[i].y);
fil = min(fil, pi[i].x);
}
}
//cout << fil << " " << lar << endl;
for(int i=s; i<=lar; i++){
if(i > cr){
ans += 2;
cr++;
}
if(nr[i] != -1)
cr = max(cr, nr[i]);
}
for(int i=s; i>=fil; i--){
if(i < cl){
ans += 2;
cl--;
}
if(nl[i] != -1)
cl = min(cl, nl[i]);
}
return ans;
}
Compilation message
books.cpp: In function 'long long int minimum_walk(std::vector<int>, int)':
books.cpp:22:36: error: 'cu' was not declared in this scope
for(int i=0; i<n; i++) ans += abs(cu - p[cu]);
^~
books.cpp:43:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i=0; i<pi.size(); i++){
~^~~~~~~~~~
