Submission #430800

#	Time	Username	Problem	Language	Result	Execution time	Memory
430800		Supersonic	Rainforest Jumps (APIO21_jumps)	C++14	100 / 100	1969 ms	42804 KiB

jumps

#include "jumps.h"

#include <bits/stdc++.h>
using namespace std;
int n;vector<int> v;
#define SIZE 262144
typedef long long ll;
vector<int> l;vector<int> r;vector<int> t;int y[200001];int pa;
int jm[200001][21];int jr[200001][21];
ll tree[2*SIZE];
int m1=-1,m1i=-1,m2=-1;
int p2[18]={1,2,4,8,16,32,64,128,256,512,1024,2048,4096,8192,16384,32768,65536,131072};
int g(int a,int p){
  if(a==-1||a+p2[p]>=n)return -1;
  if(jm[a][p]>=0)return jm[a][p];
  if(p==0){if(l[a]==-1)jm[a][p]=r[a];else if(r[a]==-1)jm[a][p]=l[a];if(v[l[a]]>v[r[a]])jm[a][p]=l[a];else jm[a][p]=r[a];return jm[a][p];}
  jm[a][p]=g(g(a,p-1),p-1);;
  return jm[a][p];
}
int gr(int a,int p){
  if(a==-1||a+p2[p]>=n)return -1;
  if(jr[a][p]>=0)return jr[a][p];
  if(p==0){jr[a][p]=r[a];return jr[a][p];}
  jr[a][p]=gr(gr(a,p-1),p-1);;
  return jr[a][p];
}
void u(int pos, int val) {
  pos += SIZE;
  tree[pos]=val;
  for (pos /= 2; pos >= 1; pos /= 2){
    tree[pos] = max(tree[2*pos], tree[2*pos+1]);
  }
}
ll q(int a, int b) {
  a += SIZE; b += SIZE;
  ll s = 0;
  while (a <= b) {
    if (a%2 == 1) s = max(s, tree[a++]);
    if (b%2 == 0) s = max(s, tree[b--]);
    a /= 2; b /= 2;
  }
  return s;
}
void init(int N, std::vector<int> H) {
  //if(N==176)exit(1);
  n=N;v=H;
  l.push_back(-1);t.push_back(0);
  for(int i=0;i<n;i++){u(i,H[i]);y[H[i]]=i;for(int j=0;j<21;j++){jm[i][j]=-1;jr[i][j]=-1;}}
  for(int i=1;i<n;i++){
    //for(auto k:t)cerr<<k<<' ';cerr<<endl;
    while(t.size()>0&&v[i]>v[t.back()])t.pop_back();
    if(t.size()==0)l.push_back(-1);
    else l.push_back(t.back());
    t.push_back(i);
  }
  reverse(v.begin(),v.end());t.clear();
  r.push_back(-1);t.push_back(0);
  for(int i=1;i<n;i++){
    while(t.size()>0&&v[i]>v[t.back()])t.pop_back();
    if(t.size()==0)r.push_back(-1);
    else r.push_back(t.back());
    t.push_back(i);
  }
  reverse(v.begin(),v.end());reverse(r.begin(),r.end());for(int i=0;i<n;i++)if(r[i]!=-1)r[i]=(n-1)-r[i];
  //cerr<<l[1]<<endl;
  //cout<<"DBG"<<endl;int td;cin>>td;while(td--){int ta,tb;cin>>ta>>tb;cout<<g(ta,tb)<<endl;}
}
int mj(int a,int c,int d,int p){
  //p=16;
  //pa++;
  //cerr<<a<<' '<<v[a]<<" | ";
  if((c<=l[a]&&l[a]<=d)||(c<=r[a]&&r[a]<=d))return 1;
  if(v[l[a]]>m2){
    p=16;
    while(p>=0&&(gr(a,p)==-1||r[jr[a][p]]==-1||r[jr[a][p]]>=c))p--;
    if(p==-1){
      if(r[a]!=-1&&r[a]<=d&&v[r[a]]<m2)return 1+mj(r[a],c,d,0);
      return -1*1e8;
    }
    return p2[p]+mj(jr[a][p],c,d,p);
  }
  while(p>=0&&(g(a,p)==-1||r[jm[a][p]]==-1||r[jm[a][p]]>=c))p--;
  if(p==-1){
    if(r[a]!=-1&&l[a]!=-1&&v[r[a]]>v[l[a]]&&v[r[a]]<m2&&r[a]<=d)return 1+mj(r[a],c,d,0);
    if(l[a]!=-1&&l[a]<=d&&v[l[a]]<m2)return 1+mj(l[a],c,d,0);
    if(r[a]!=-1&&r[a]<=d&&v[r[a]]<m2)return 1+mj(r[a],c,d,0);
    return -1*1e8;
  }
  //cerr<<a<<' '<<p<<' '<<r[g(a,p)]<<endl;
  return p2[p]+mj(jm[a][p],c,d,p);
}
int minimum_jumps(int a, int b, int c, int d) {
  //cerr<<v[a]<<' '<<v[b]<<' '<<v[c]<<' '<<v[d]<<endl;
  m2=q(c,d);pa=0;
  int x=a-1;
  for (int e=p2[15];e>=1;e/=2) {
    while(q(x+e,b)>m2)x+=e;
  }
  x++;if(x>b)return -1;
  m1=q(x,b);m1i=y[m1];
  int tj=max(mj(m1i,c,d,16),-1);//cerr<<pa<<' ';
  return tj;
}

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