제출 #593851

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
593851		Valaki2	Shortcut (IOI16_shortcut)	C++14	0 / 100	1 ms	340 KiB

shortcut

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

#define n N
#define c C

#define int long long

const int inf = 1e16 + 42;
const int maxn = 500; // !!!!!

int n, c;
vector<int> v, nxt_dst, prv_dst;
vector<vector<int> > dist;
int ans;
int pref_max[maxn + 2];
int suff_max[maxn + 2];
int pref_d[maxn + 2];
int suff_d[maxn + 2];
int bet_d[maxn + 2][maxn + 2];

int bb(int a, int b) {
    int res = 0;
    int l = b, r = b;
    while(l >= a) {
        while(dist[l][r] > dist[l][a] + c + dist[b][r]) {
            res = max(res, v[l] + v[r] + dist[l][a] + c + dist[b][r]);
            r--;
        }
        res = max(res, bet_d[l][r]);
        l--;
    }
    return res;
}

int solve_for(int a, int b) {
    int res = 0;
    // aa
    res = max(res, pref_d[a]);
    // ab
    for(int i = a; i <= b; i++) {
        res = max(res, v[i] + pref_max[a] + min(dist[i][a], dist[i][b] + c));
    }
    // ac
    res = max(res, pref_max[a] + suff_max[b] + min(c, dist[a][b]));
    // bb
    res = max(res, bb(a, b));
    // bc
    for(int i = a; i <= b; i++) {
        res = max(res, v[i] + suff_max[b] + min(dist[i][b], dist[i][a] + c));
    }
    // cc
    res = max(res, suff_d[b]);
    //cout << a << " " << b << ": " << res << "\n";
    return res;
}

int solve() {
    dist.assign(1 + n + 1, vector<int> (1 + n + 1, 0));
    for(int i = 1; i <= n; i++) {
        int sum = 0;
        for(int j = i; j <= n; j++) {
            dist[i][j] = dist[j][i] = sum;
            sum += nxt_dst[j];
        }
    }
    pref_max[0] = -inf;
    pref_d[0] = -inf;
    for(int i = 1; i <= n; i++) {
        pref_d[i] = max(pref_d[i - 1], pref_max[i - 1] + v[i]);
        pref_max[i] = max(v[i], pref_max[i - 1] + prv_dst[i]);
    }
    suff_max[n + 1] = -inf;
    suff_d[n + 1] = -inf;
    for(int i = n; i >= 1; i--) {
        suff_d[i] = max(suff_d[i + 1], suff_max[i + 1] + v[i]);
        suff_max[i] = max(v[i], suff_max[i + 1] + nxt_dst[i]);
    }
    for(int i = 1; i <= n; i++) {
        int maxi = v[i] + nxt_dst[i];
        for(int j = i + 1; j <= n; j++) {
            bet_d[i][j] = maxi + v[j];
            maxi = max(maxi, v[j]);
            maxi += nxt_dst[j];
        }
    }
    ans = inf;
    for(int i = 1; i <= n; i++) {
        for(int j = i + 1; j <= n; j++) {
            ans = min(ans, solve_for(i, j));
        }
    }
    return ans;
}

#undef n
#undef c
int find_shortcut(signed n, vector<signed> l, vector<signed> d, signed c) {
    N = n;
    C = c;
    v.assign(1 + N + 1, 0);
    nxt_dst.assign(1 + N + 1, 0);
    prv_dst.assign(1 + N + 1, 0);
    for(int i = 0; i < N; i++) {
        v[i + 1] = d[i];
        if(i != N - 1) {
            nxt_dst[i + 1] = l[i];
            prv_dst[i + 2] = l[i];
        }
    }
    return solve();
}

• Subtask 1: 0 / 9
• Subtask 2: 0 / 14
• Subtask 3: 0 / 8
• Subtask 4: 0 / 7
• Subtask 5: 0 / 33
• Subtask 6: 0 / 22
• Subtask 7: 0 / 4
• Subtask 8: 0 / 3