Submission #349180

#	Time	Username	Problem	Language	Result	Execution time	Memory
349180		dgq	Rice Hub (IOI11_ricehub)	C++17	100 / 100	19 ms	1788 KiB

ricehub

#include "ricehub.h"
#include <cmath>

using namespace std;

bool poss(int len, long long budget, int *x, int n) {
  long long cost = 0;
  int a = 0;
  int b = len - 1;
  int mid = (a + b) / 2;
  long long left = 0;
  long long right = 0;
  for (int i = a; i <= b; i++) {
    cost += abs(x[i] - x[mid]);
  }
  left = mid - a;
  right = b - mid;
  if (cost <= budget) return true;
  while (b + 1 < n) {
    cost -= x[mid] - x[a];
    cost += left * (x[mid + 1] - x[mid]);
    cost -= right * (x[mid + 1] - x[mid]);
    mid++;
    a++;
    b++;
    cost += x[b] - x[mid];
    if (cost <= budget) return true;
  }
  return false;
}

int besthub(int n, int l, int x[], long long budget) {
  int a = 1;
  int b = n;
  int res = -1;
  while (a <= b) {
    int mid = (a + b) / 2;
    if (poss(mid, budget, x, n)) {
      res = mid;
      a = mid + 1;
    } else {
      b = mid - 1;
    }
  }
  return res;
}

• Subtask 1: 17 / 17
• Subtask 2: 25 / 25
• Subtask 3: 26 / 26
• Subtask 4: 32 / 32