Submission #744804

#	Time	Username	Problem	Language	Result	Execution time	Memory
744804		Mauve	Rainforest Jumps (APIO21_jumps)	C++14	37 / 100	4078 ms	27516 KiB

jumps

#include "jumps.h"
using namespace std;
#include<bits/stdc++.h>
#define pb push_back
int n,m,l,r,i,j,ii,jj,k,h[21][200002],subtask;
vector<int> v[200006];
int asuu(int l, int r){
	int k=r-l+1;
	k = 31 - __builtin_clz(k);
	return max(h[k][l],h[k][r-(1<<k)+1]);
}
void init(int N, std::vector<int> H){
	n=N;
	for(i=0;i<n;i++){
		h[0][i]=H[i];
		if(H[i]!=i+1) subtask=1;
	}
	for(j=1;j<=20;j++)
	for(i=0;i<n;i++){
		l=h[j-1][i];
		if(i+(1<<(j-1))<n) h[j][i]=max(l,h[j-1][i+(1<<(j-1))]);
	}
	for(i=0;i<n;i++){
		if(i!=0 && asuu(0,i-1)>H[i]){
			l=0;
			r=i-1;
			while(r-l>1){
				m=(r+l)/2;
				if(asuu(m+1,r)>H[i]) l=m+1;
				else r=m;
			}
			if(H[r]>H[i]) k=r;
			else k=l;
			v[i].pb(k);
		}
		if(i!=n-1 && asuu(i+1,n-1) > H[i]){
			l=i+1;
			r=n-1;
			while(r-l>1){
				m=(r+l)/2;
				if(asuu(l,m)>H[i]) r=m;
				else l=m+1;
			}
			if(H[l]>H[i]) k=l;
			else k=r;
			v[i].pb(k);
		}
	}
}
 
int minimum_jumps(int A, int B, int C, int D) {
	
	if(subtask==0){
		
		if(A>D) return -1;
		else return C-B;
		
	}
	
	int dist[200005];
	queue<int> q;
	memset(dist,-1,sizeof(dist));
	for(i=A;i<=B;i++){
		q.push(i);
		dist[i]=0;
	}
	while(!q.empty()){
		int node= q.front();
		q.pop();
		for(i=0;i<v[node].size();i++)
		if(dist[v[node][i]]==-1){
			dist[v[node][i]]=dist[node]+1;
			if(v[node][i]>=C && v[node][i]<=D) return dist[v[node][i]];
			q.push(v[node][i]);
		}
	}
	return -1;
}

Compilation message (stderr)

jumps.cpp: In function 'int minimum_jumps(int, int, int, int)':
jumps.cpp:70:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   70 |   for(i=0;i<v[node].size();i++)
      |           ~^~~~~~~~~~~~~~~

• 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