Submission #73680

#	Time	Username	Problem	Language	Result	Execution time	Memory
73680		aquablitz11	고대 책들 (IOI17_books)	C++14	50 / 100	329 ms	12396 KiB

books

#include <bits/stdc++.h>
#include "books.h"
using namespace std;

using ll = long long;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using plpii = pair<ll, pii>;

const int N = 1e6+10;
const ll INF = 1e9;

int qs[N];

ll minimum_walk(vector<int> p, int s)
{
    int n = p.size();
    bool ok = true;
    for (int i = 0; i < n; ++i) if (p[i] != i) {
        ok = false;
        break;
    }
    if (ok) return 0;
    ll dist = 0;
    for (int i = 0; i < n; ++i) {
        if (p[i] == -1) continue;
        if (p[i] == i) continue;
        int u = i;
        while (p[u] != -1) {
            int v = p[u];
            dist += abs(u-v);
            p[u] = -1;
            qs[min(u, v)] += 1;
            qs[max(u, v)] -= 1;
            u = v;
        }
    }
    int last = -1;
    if (p[s] == s) {
        int mn = INF;
        for (int i = 0; i < n; ++i) {
            if (p[i] == -1)
                mn = min(mn, abs(i-s));
        }
        dist += 2*mn;
    }
    for (int i = 0; i < n; ++i) {
        if (i > 0) qs[i] += qs[i-1];
        if (last != -1 && p[i] == -1) {
            dist += 2*(i-last);
            last = -1;
        }
        if (qs[i] == 0 && p[i] == -1)
            last = i;
    }

    return dist;
}

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