Submission #569201

#	Time	Username	Problem	Language	Result	Execution time	Memory
569201		Turkhuu	Rainforest Jumps (APIO21_jumps)	C++17	8 / 100	4086 ms	33944 KiB

jumps

#include "jumps.h"
#include <bits/stdc++.h>
using namespace std;
const int L = 18;
int n;
vector<int> a, d;
vector<vector<int>> anc;
void init(int N, vector<int> H){
  n = N, a = H;
  d.resize(n, -1);
  anc.assign(n, vector<int>(L, -1));
  vector<int> idx(n);
  for(int i = 0; i < n; i++){
    idx[--a[i]] = i;
  }
  set<int> s;
  for(int i = n - 1; i >= 0; i--){
    auto j = s.lower_bound(idx[i]);
    int l = -1, r = -1;
    if(j != s.end()){
      r = a[*j];
    }
    if(j != s.begin()){
      l = a[*prev(j)];
    }
    if(l != -1 || r != -1){
      if(l > r){
        anc[i][0] = l;
        if(r != -1){
          d[i] = r;
        }
      } else{
        anc[i][0] = r;
        if(l != -1){
          d[i] = l;
        }
      }
    }
    s.insert(idx[i]);
  }
  for(int j = 1; j < L; j++){
    for(int i = 0; i < n; i++){
      if(anc[i][j - 1] != -1){
        anc[i][j] = anc[anc[i][j - 1]][j - 1];
      }
    }
  }
}
int minimum_jumps(int A, int B, int C, int D){
  int ans = -1;
  for(int S = A; S <= B; S++){
    for(int E = C; E <= D; E++){
      int H = a[S], G = a[E], c = 0;
      while(H != -1 && H < G){
        int j = -1;
        for(int i = 0; i < L; i++){
          if(anc[H][i] != -1 && anc[H][i] <= G){
            j = i;
          }
        }
        if(j != -1){
          H = anc[H][j];
          c += 1 << j;
        } else{
          if(H != -1){
            H = d[H];
            c++;
          }
        }
      }
      if(H == G){
        if(ans == -1 || c < ans){
          ans = c;
        }
      }
    }
  }
  return ans;
}

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