Submission #1228420

#	Time	Username	Problem	Language	Result	Execution time	Memory
1228420		LucaIlie	Aliens (IOI16_aliens)	C++20	0 / 100	0 ms	328 KiB

aliens

#include "aliens.h"
#include <vector>
#include <stdio.h>
#include <algorithm>

using namespace std;

struct interval {
    int l, r;
    bool operator < (interval a) {
        if (l == a.l)
            return r > a.r;
        return l < a.l;
    }
};

const int MAX_N = 1e5;
const long long INF = 1e18;
int cnt[MAX_N + 1];
long long dp[MAX_N + 1];
interval v[MAX_N + 1];

long long take_photos(int n, int m, int k, vector<int> R, vector<int> C) {
    vector<interval> rc(n);
    for (int i = 0; i < n; i++) {
        if (R[i] > C[i])
            swap(R[i], C[i]);
        C[i]++;
        rc[i] = {R[i], C[i]};
    }

    sort(rc.begin(), rc.end());

    n = 0;
    int maxR = -1;
    for (interval a: rc) {
        if (a.r > maxR) {
            v[++n] = a;
            maxR = a.r;
        }
    }

    long long lb = 0, rb = 1e12;
    while (rb - lb > 1) {
        long long coef = (lb + rb) / 2;

        for (int i = 1; i <= n; i++) {
            dp[i] = INF;
            for (int j = 1; j <= i; j++) {
                long long len = (v[i].r - v[j].l);
                long long over = max(0, (v[j - 1].r - v[j].l));

                if (dp[j - 1] + len * len - over * over < dp[i]) {
                    dp[i] = dp[j - 1] + len * len - over * over + coef;
                    cnt[i] = cnt[j - 1] + 1;
                }
            }
        }

        if (cnt[n] > k)
            lb = coef;
        else
            rb = coef;
    }
    long long coef = rb;
    for (int i = 1; i <= n; i++) {
        dp[i] = INF;
        for (int j = 1; j <= i; j++) {
            long long len = (v[i].r - v[j].l);
            long long over = max(0, (v[j - 1].r - v[j].l));

            if (dp[j - 1] + len * len - over * over < dp[i]) {
                dp[i] = dp[j - 1] + len * len - over * over + coef;
                cnt[i] = cnt[j - 1] + 1;
            }
        }
    }

    return dp[n] - coef * k;
}

Compilation message (stderr)

aliens.h:1:9: warning: #pragma once in main file
    1 | #pragma once
      |         ^~~~
aliens_c.h:1:9: warning: #pragma once in main file
    1 | #pragma once
      |         ^~~~

• Subtask 1: 0 / 4
• Subtask 2: 0 / 12
• Subtask 3: 0 / 9
• Subtask 4: 0 / 16
• Subtask 5: 0 / 19
• Subtask 6: 0 / 40