Submission #1178797

#	Time	Username	Problem	Language	Result	Execution time	Memory
1178797		ericl23302	Aliens (IOI16_aliens)	C++20	0 / 100	5 ms	328 KiB

aliens

#include "aliens.h"

#include <iostream>
#include <algorithm>
#include <utility>
#include <climits>
#include <set>
using namespace std;

long long sq(long long a) {
    return a * a;
}
long long sq(int a) {
    return (long long)(a) * a;
}

long long take_photos(int n, int m, int k, std::vector<int> r, std::vector<int> c) {
    set<pair<int, int>> curPoints;
    for (int i = 0; i < n; ++i) curPoints.emplace(min(r[i], c[i]), max(r[i], c[i]));
    long long bestVal = LLONG_MAX / 2;
    while (true) {
        bestVal = LLONG_MAX / 2;
        auto curStart = curPoints.end(), curEnd = curPoints.end();
        for (auto i = curPoints.begin(); i != curPoints.end(); ++i) {
            for (auto j = next(i); j != curPoints.end(); ++j) {
                auto a = *i, b = *j;
                pair<int, int> newRange = make_pair(min(a.first, b.first), max(a.second, b.second)), overlap = make_pair(max(a.first, b.first), min(a.second, b.second));
                long long newDist = sq(newRange.second - newRange.first + 1) - sq(a.second - a.first + 1) - sq(b.second - b.first + 1) + sq(max(0, overlap.second - overlap.first + 1));
                if (newDist < bestVal) {
                    bestVal = newDist;
                    curStart = i; 
                    curEnd = j;
                }
            }
        }

        if (curPoints.size() > k) {
            auto a = *curStart, b = *curEnd;
            pair<int, int> newRange = make_pair(min(a.first, b.first), max(a.second, b.second));
            curPoints.erase(curStart);
            curPoints.erase(curEnd);
            curPoints.insert(newRange);
        } else break;
    }

    long long res = 0;
    pair<int, int> prev = make_pair(-1, -1), cur = make_pair(-1, -1);
    for (auto i = curPoints.begin(); i != curPoints.end(); ++i) {
        auto a = *i;
        if (a.first != cur.first) {
            res += sq(cur.second - cur.first + 1) - sq(max(min(cur.second, prev.second) - max(cur.first, prev.first) + 1, 0));
            prev = cur;
            cur = a;
        } else cur.second = max(cur.second, a.second);
    }
    res += sq(cur.second - cur.first + 1) - sq(max(min(cur.second, prev.second) - max(cur.first, prev.first) + 1, 0));

    return res;
}

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