Submission #569370

#	Time	Username	Problem	Language	Result	Execution time	Memory
569370		Turkhuu	Rainforest Jumps (APIO21_jumps)	C++17	23 / 100	1338 ms	53692 KiB

jumps

#include "jumps.h"
#include <bits/stdc++.h>
using namespace std;
const int L = 18;
int n;
vector<int> a;
vector<vector<int>> lo, hi;
void init(int N, vector<int> H){
  n = N, a = H;
  lo.assign(n, vector(L, -1));
  hi.assign(n, vector(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 || l >= r)){
      lo[i][0] = r;
      hi[i][0] = l;
    } else{
      lo[i][0] = l;
      hi[i][0] = r;
    }
    s.insert(idx[i]);
  }
  for(int j = 1; j < L; j++){
    for(int i = 0; i < n; i++){
      if(lo[i][j - 1] != -1){
        lo[i][j] = lo[lo[i][j - 1]][j - 1];
      }
      if(hi[i][j - 1] != -1){
        hi[i][j] = hi[hi[i][j - 1]][j - 1];
      }
    }
  }
}
int minimum_jumps(int A, int B, int C, int D){
  int H = a[A], G = a[C], c = 0;
  for(int i = L - 1; i >= 0; i--){
    if(hi[H][i] != -1 && hi[H][i] <= G){
      H = hi[H][i];
      c += 1 << i;
    }
  }
  for(int i = L - 1; i >= 0; i--){
    if(lo[H][i] != -1 && lo[H][i] <= G){
      H = lo[H][i];
      c += 1 << i;
    }
  }
  if(H != G){
    c = -1;
  }
  return c;
}

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