Submission #529133

#	Time	Username	Problem	Language	Result	Execution time	Memory
529133		msg555	Aliens (IOI16_aliens)	C++14	25 / 100	2069 ms	448 KiB

aliens

#include "aliens.h"

#include <vector>
#include <algorithm>
#include <iostream>

using namespace std;

long long squared(int x) {
  return 1ll * x * x;
}

long long take_photos(int N, int M, int K, vector<int> R, vector<int> C) {
  vector<pair<int, int> > A;
  for (int i = 0; i < N; i++) {
    int ri = R[i];
    int ci = C[i];
    if (ri > ci) swap(ri, ci);
    A.push_back(make_pair(ci, ci - ri));
  }
  sort(A.begin(), A.end());

  int j = 0;
  for (auto p : A) {
    while (j > 0 && p.second >= A[j - 1].second + p.first - A[j - 1].first) {
      --j;
    }
    A[j++] = p;
  }
  A.resize(j);
  N = j;

  long long INF = squared(M + 1);

  vector<long long> DP(N + 1, INF);
  DP[0] = 0;

  for (int k = 0; k < K; k++) {
    for (int i = 1; i < N; i++) {
      DP[i] -= squared(max(0, 1 + A[i].second - A[i].first + A[i - 1].first));
    }

    for (int i = N; i > 0; i--) {
      DP[i] = INF;
      for (int j = 0; j < i; j++) {
        DP[i] = min(
          DP[i],
          DP[j] + squared(1 + A[j].second + A[i - 1].first - A[j].first)
        );
      }
    }
  }

  return DP[N];
}

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