Submission #568248

#	Time	Username	Problem	Language	Result	Execution time	Memory
568248		Aktan	Rainforest Jumps (APIO21_jumps)	C++14	37 / 100	4026 ms	5040 KiB

jumps

#include "jumps.h"
#include <bits/stdc++.h>
#ifndef EVAL
#include "stub.cpp"
#endif
using namespace std;
int n;
bool h=0;
vector<int> a;
int b[200005],c[200005];
void init(int N, vector<int> H) {
	n=N;
	a=H;
	for(int i=0;i<n;i++){
		if(i){
			if(H[i]!=H[i-1]+1){
				h=1;
				break;
			}	
		}
	}
	if(h==0){
		return;
	}
	deque<int> s;
	for(int i=0;i<n;i++){
		while(!s.empty() && a[s.back()]<a[i]){
			s.pop_back();
		}
		if(s.empty()){
			b[i]=-1;
		}
		else{
			b[i]=s.back();
		}
		s.push_back(i);
	}
	s.clear();
	for(int i=n-1;i>=0;i--){
		while(!s.empty() && a[s.back()]<a[i]){
			s.pop_back();
		}
		if(s.empty()){
			c[i]=-1;
		}
		else{
			c[i]=s.back();
		}
		s.push_back(i);
	}
}
int ans[200005];
int minimum_jumps(int A, int B, int C, int D) {
  if(h==0){
  	return C-B;
  }
  else{
  	for(int i=0;i<n;i++){
  		ans[i]=1e9;
	}
	queue<int> q;
	for(int i=A;i<=B;i++){
		ans[i]=0;
		q.push(i);
	}
	while(!q.empty()){
		int to=q.front();
		q.pop();
		if(b[to]!=-1 && ans[b[to]]>ans[to]+1){
			ans[b[to]]=ans[to]+1;
			q.push(b[to]);
		}
		if(c[to]!=-1 && ans[c[to]]>ans[to]+1){
			ans[c[to]]=ans[to]+1;
			q.push(c[to]);
		}
	}
	int k=1e9;
	for(int i=C;i<=D;i++){
		k=min(k,ans[i]);
	}
	if(k==1e9){
		return -1;
	}
	else{
		return k;	
	}
  }
  
}

• 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