Submission #937324

#	Time	Username	Problem	Language	Result	Execution time	Memory
937324		snpmrnhlol	Ancient Books (IOI17_books)	C++17	50 / 100	96 ms	16080 KiB

books

#include "books.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll N = 1e6;
const ll inf = 1e18;
ll ps[N + 1];
long long minimum_walk(std::vector<int> p, int s) {
    int n = p.size();
    ll ans = 0;
    ll mx = -inf;
    ll mn = inf;
    ll mx2 = -inf;
    ll mn2 = inf;
    bool ok = 0;
    for(ll i = 0;i < n;i++){
        ans+=abs(i - p[i]);
        if(i != p[i]){
            ok = 1;
            if(i < p[i]){
                ps[p[i]]--;
                ps[i]++;
            }
            if(i <= s){
                mx = max(mx,i);
            }
            if(i >= s){
                mn = min(mn,i);
            }
            mx2 = max(mx2,i);
            mn2 = min(mn2,i);
        }
    }
    if(ok == 0)return ans;
    ll sum = 0;
    for(int i = mn2;i < mx2;i++){
        sum+=ps[i];
        if(sum == 0)ans+=2;
    }
    if(mx == -inf || mn == inf){
        ans+=2*min(s - mx,mn - s);
    }
	return ans;
}
/**
7 3
2 1 0 3 6 5 4
**/

• Subtask 1: 12 / 12
• Subtask 2: 10 / 10
• Subtask 3: 28 / 28
• Subtask 4: 0 / 20
• Subtask 5: 0 / 30