Submission #893207

#	Time	Username	Problem	Language	Result	Execution time	Memory
893207		vjudge1	Ancient Books (IOI17_books)	C++17	0 / 100	0 ms	348 KiB

books

#include "books.h"

#include <bits/stdc++.h>

using namespace std;

using ll = long long;
using vll = vector<ll>;
using vi = vector<int>;
using ii = pair<int, int>;

struct UF {
    vi e;
    UF(int N) : e(N, -1) {}
    int repr(int u) {
        while(e[u] >= 0) u = e[u];
        return u;
    }

    int join(int u, int v) {
        u = repr(u);
        v = repr(v);
        if(u == v) return 0;
        if(e[u] >= e[v]) swap(u, v);
        e[u] += e[v];
        e[v] = u;
        return 1;
    }
};

long long minimum_walk(vi p, int s) {
    int n = p.size();
    vi ip(n);
    for(int i = 0; i < n; ++i)
        ip[p[i]] = i;
    using ll = long long;
    ll re = 0, nrcic = 0;
    vi viz(n, 0), are_st(n, 0);
    for(int i = 0; i < n; ++i) {
        if(!viz[i]) {
            int u = i, mi = i;
            while(!viz[u]) {
                viz[u] = 1;
                u = p[u];
                mi = min(mi, u);
            }
            u = i;
            do {
                if(u > mi) are_st[u] = 1;
                u = p[u];
            } while(u != i);
            ++nrcic;
        }
    }
    vll dp(n, 0);
    for(int i = 1; i < n; ++i) {
        if(are_st[i]) dp[i] = dp[i - 1];
        else dp[i] = 2 + dp[i - 1];
    }
    for(int i = 0; i < n; ++i) {
        re += abs(p[i] - i);
    }
    for(int i = n - 1; i >= 0; --i) {
        if(p[i] != i) {
            re += dp[i];
            break;
        }
    }
    return re;
}

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