Submission #430680

#	Time	Username	Problem	Language	Result	Execution time	Memory
430680		Supersonic	Rainforest Jumps (APIO21_jumps)	C++14	4 / 100	2401 ms	26176 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 jm[200001][21];
ll tree[2*SIZE];
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){jm[a][p]=max(l[a],r[a]);return jm[a][p];}
  jm[a][p]=g(g(a,p-1),p-1);;
  return jm[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;}
  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];
  //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){
  //cerr<<a<<' '<<v[a]<<endl;
  int p=17;
  if(c<=a&&a<=d)return 0;
  if((c<=l[a]&&l[a]<=d)||(c<=r[a]&&r[a]<=d))return 1;
  while(p>=0&&(g(a,p)==-1||r[g(a,p)]==-1||r[g(a,p)]>=c))p--;
  if(p==-1){
    if(r[a]!=-1&&r[a]<=d)return 1+mj(r[a],c,d);
    if(l[a]!=-1&&l[a]<=d)return 1+mj(l[a],c,d);
    return -1;
  }
  //cerr<<a<<' '<<p<<' '<<r[g(a,p)]<<endl;
  int th=mj(g(a,p),c,d);
if(th<0)return -1;
return p2[p]+th;
}
int minimum_jumps(int a, int b, int c, int d) {
  int m1=-1,m1i=-1,m2=-1,m2i=-1;
  m2=q(c,d);
  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];
  //for(int i=b;i>=a;i--){if(v[i]>m2)break;if(v[i]>m1){m1=v[i];m1i=i;}}
  //for(int i=m1i;i<=m2i;i++)if(v[i]>m2)return -1;
  //if(m1i==-1||m2i==-1)return -1;
  //for(auto k:l)cerr<<k<<' ';cerr<<endl;
  //for(auto k:r)cerr<<k<<' ';cerr<<endl;
  //if(m1i==-1)return -1;
  return max(mj(m1i,c,d),-1);
  int s=0;
  while(1){
    s++;
    //cerr<<m1<<' '<<l[m1]<<' '<<r[m1]<<endl;
    if((c<=l[m1i]&&l[m1i]<=d)||(c<=r[m1i]&&r[m1i]<=d)){return s;}
    if(l[m1i]==-1&&r[m1i]==-1)return -1;
    else if(r[m1i]==-1)m1i=l[m1i];
    else if(l[m1i]==-1)m1i=r[m1i];
    else if(v[r[m1i]]>m2)m1i=l[m1i];
    else if(v[l[m1i]]>m2)m1i=r[m1i];
    else if(v[l[m1i]]>v[r[m1i]])m1i=l[m1i];
    else m1i=r[m1i];
  }
  exit(1);
}

Compilation message (stderr)

jumps.cpp: In function 'int minimum_jumps(int, int, int, int)':
jumps.cpp:76:26: warning: unused variable 'm2i' [-Wunused-variable]
   76 |   int m1=-1,m1i=-1,m2=-1,m2i=-1;
      |                          ^~~

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