Submission #624897

#	Time	Username	Problem	Language	Result	Execution time	Memory
624897		brucecccccc	Boxes with souvenirs (IOI15_boxes)	C++14	100 / 100	860 ms	293872 KiB

boxes

#include "boxes.h"
#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

const int MAXN = 1e7+5;
ll f[MAXN], b[MAXN];

ll delivery(int N, int K, int L, int p[]) {  
  fill(f, f+MAXN, -1);
  fill(b, b+MAXN, -1);
  int i = 0;
  while (i < N && f[i] == -1) {
    f[i] = p[i] + min(p[i], L - p[i]);
    for (int j = i + K; j < N; j += K) {
      f[j] = f[j-K] + p[j] + min(p[j], L - p[j]);
    }
    i++;
  }

  i = N-1;
  while (i >= 0 && b[i] == -1) {
    b[i] = L - p[i] + min(p[i], L - p[i]);
    for (int j = i - K; j >= 0; j -= K) {
      b[j] = b[j+K] + L - p[j] + min(p[j], L - p[j]);
    }
    i--;
  }

  ll ans = min(f[N-1], b[0]);
  i=0;
  for (; i < N - 1; i++) {
    ans = min(ans, f[i] + b[i+1]);
  }

  return ans;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 15 / 15
• Subtask 4: 15 / 15
• Subtask 5: 20 / 20
• Subtask 6: 30 / 30