Submission #1101276

#	Time	Username	Problem	Language	Result	Execution time	Memory
1101276		blackslex	Rainforest Jumps (APIO21_jumps)	C++17	37 / 100	4026 ms	18112 KiB

jumps

#include "jumps.h"
#include <vector>
#include<bits/stdc++.h>

using namespace std;
using pii = pair<int, int>;

const int MxN = 2e5 + 5;
int n, l[MxN], r[MxN];
vector<int> h, v[MxN];
vector<pii> c;
bool sub1 = 1;

void init(int N, std::vector<int> H) {
  n = N; h = H;
  stack<int> st;
  for (int i = 0; i < n; i++) {
    if (h[i] != i + 1) sub1 = 0;
    c.emplace_back(h[i], i);
  }
  sort(c.begin(), c.end());
  for (int i = 0; i < n; i++) {
    l[i] = -1;
    while (!st.empty() && h[i] > h[st.top()]) st.pop();
    if (!st.empty()) l[i] = st.top();
    st.emplace(i);
  }
  while (!st.empty()) st.pop();
  for (int i = n - 1; i >= 0; i--) {
    r[i] = -1;
    while (!st.empty() && h[i] > h[st.top()]) st.pop();
    if (!st.empty()) r[i] = st.top();
    st.emplace(i);
  }
  for (int i = 0; i < n; i++) {
    if (~l[i]) v[l[i]].emplace_back(i);
    if (~r[i]) v[r[i]].emplace_back(i);
  }
}

int minimum_jumps(int A, int B, int C, int D) {
  if (sub1) return C - B;
  vector<int> dp(n + 5, 1e9);
  for (int i = A; i <= B; i++) dp[i] = 0;
  for (auto &[x, y]: c) {
    for (auto &e: v[y]) dp[y] = min(dp[y], dp[e] + 1);
  }
  int ans = 1e9;
  for (int i = C; i <= D; i++) ans = min(ans, dp[i]);
  return (ans == 1e9 ? -1 : ans);
}

• Subtask 1: 4 / 4
• Subtask 2: 8 / 8
• Subtask 3: 13 / 13
• Subtask 4: 12 / 12
• Subtask 5: 0 / 23
• Subtask 6: 0 / 21
• Subtask 7: 0 / 19