Submission #1208860

#	Time	Username	Problem	Language	Result	Execution time	Memory
1208860		aykhn	The short shank; Redemption (BOI21_prison)	C++20	35 / 100	2095 ms	38236 KiB

prison

#include<bits/stdc++.h>

using namespace std;

#define int long long
#define inf 0x3F3F3F3F

const int MXN = 5e5 + 5;
const int LOG = 20;

int n, D, T;
int arr[MXN], L[MXN];
int dp[MXN], ndp[MXN], add[MXN];

void solve(int l, int r, int lx, int rx)
{
  if (l > r) return;
  int mid = (l + r) >> 1, cost = 0;
  array<int, 2> best = {inf, -1};
  for (int i = mid; i >= lx; i--)
  {
    if (L[i] && L[i] >= lx) add[L[i]]++;
    cost += add[i], add[i] = 0;
    best = min(best, {cost + dp[i - 1], i});
  }
  ndp[mid] = best[0];
  solve(l, mid - 1, lx, best[1]);
  solve(mid + 1, r, best[1], rx);
}

void _()
{
  cin >> n >> D >> T;
  for (int i = 1; i <= n; i++) cin >> arr[i];
  {
    multiset<array<int, 2>> ms;
    multiset<int> mx;
    for (int i = 1; i <= n; i++)
    {
      ms.insert({arr[i] - i, i});
      mx.insert(i);
      while (!ms.empty() && T - i < (*ms.rbegin())[0]) 
      {
        mx.erase(mx.find((*ms.rbegin())[1]));
        ms.erase(prev(ms.end()));
      }
      if (!mx.empty()) L[i] = *mx.rbegin();
    }
  }
  fill(dp + 1, dp + n + 1, inf);
  for (int i = 0; i <= D; i++)
  {
    fill(ndp + 1, ndp + n + 1, inf);
    solve(1, n, 1, n);
    for (int i = 0; i <= n; i++) dp[i] = min(dp[i], ndp[i]);
  }
  cout << dp[n] << '\n';
}
signed main()
{
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  int t = 1;
  // cin >> t;
  while (t--) _();
}

• Subtask 1: 15 / 15
• Subtask 2: 0 / 10
• Subtask 3: 20 / 20
• Subtask 4: 0 / 10
• Subtask 5: 0 / 25
• Subtask 6: 0 / 20