#include "books.h"
#include <bits/stdc++.h>
using namespace std;
int r = -1, l = 1000001;
vector<int> p;
bool in[1000001];
int cl = -1;
int s;
int cr = 1000001;
void go(int v){
if(in[v] == 1){
return;
}
if(v <= s){
cl = max(cl, v);
} else {
cr = min(cr, v);
}
in[v] = 1;
r = max(r, v);
go(p[v]);
}
long long minimum_walk(vector<int> p, int s) {
::p = p;
::s = s;
int q = 0;
long long ans = 0;
for(int i = 0; i < p.size(); i++){
ans += (long long)abs(i - p[i]);
if(in[i] || p[i] == i) continue;
l = min(l, i);
if(r < i && r != -1){
ans += (long long)(i - r) * 2;
}
go(i);
}
if(s < l && l != 1000001){
ans += (l - s) * 2;
} else if(s > r &&r != -1){
ans += (r - s) * 2;
}else if(cl != -1 && cr != 1000001) ans +=2 * min(s - cl, cr - s);
else if(cl != -1) ans += 2 * (s - cl);
else if(cr != 1000001) ans += 2 * (cr - s);
return ans;
}
int main(){
int n, s;
cin>>n>>s;
vector<int> p;
while(n--){
int k;
cin>>k;
p.push_back(k);
}
cout<<minimum_walk(p, s);
}
Compilation message
books.cpp: In function 'long long int minimum_walk(std::vector<int>, int)':
books.cpp:29:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i = 0; i < p.size(); i++){
~~^~~~~~~~~~
books.cpp:27:6: warning: unused variable 'q' [-Wunused-variable]
int q = 0;
^
/tmp/ccifwMc8.o: In function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'
/tmp/cczldkeZ.o:books.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status
