Submission #1227790

#	Time	Username	Problem	Language	Result	Execution time	Memory
1227790		abdelhakim	Rainforest Jumps (APIO21_jumps)	C++20	48 / 100	488 ms	56872 KiB

jumps

#include "jumps.h"
#include <bits/stdc++.h>
#define ll long long
#define inf (ll)(1e15) 
#define dbg(x) cerr <<#x << ' ' << x <<endl;
using namespace std;
ll n;
vector<ll> h;
vector<pair<ll,ll>> mn;
vector<ll> ind;
vector<ll> limn;
vector<vector<ll>> nqqz;
ll maxn=2e5;
vector<ll> tree(4*maxn+3);
void update(ll node, ll l, ll r, ll pos, ll val)
{
  if(pos < l || pos > r)return;
  if(l==r)
  {
    tree[node]=val;
    return;
  }
  ll mid=(l+r)/2;
  update(node*2+1,l,mid,pos,val);
  update(node*2+2,mid+1,r,pos,val);
  tree[node]=max(tree[node*2+1],tree[node*2+2]);
}
ll query(ll node, ll l, ll r, ll x, ll y)
{
  if(max(l,x) > min(r,y))return 0;
  if(x<=l && r<=y)return tree[node];
  ll mid=(l+r)/2;
  return max(query(node*2+1,l,mid,x,y),query(node*2+2,mid+1,r,x,y));
}
void init(int N, std::vector<int> H) 
{
  n=N;
  for (int i=0;i<n;i++) h.push_back(H[i]);
  mn.resize(n+1);
  stack<ll> s;
  for (int i=0;i<n;i++)
  {
    while(s.size() && (s.top() < h[i]))
    {
      s.pop();
    }
    if(s.size())
    {
      mn[h[i]].first=s.top();
    }
    s.push(h[i]);
  }
  while(s.size())s.pop();
  for (int i=n-1;i>=0;i--)
  {
    while(s.size() && (s.top() < h[i]))
    {
      s.pop();
    }
    if(s.size())
    {
      mn[h[i]].second=s.top();
    }
    s.push(h[i]);
  }
  ind.resize(n+1);
  for (int i=0;i<n;i++)
  {
    ind[h[i]]=i;
    update(0,0,n-1,i,h[i]);
  }
  limn.resize(n+1);
  for (int i=n-1;i>=0;i--)
  {
    if(mn[h[i]].second!=0)
    {
      limn[h[i]]=1+limn[mn[h[i]].second];
    }
  }
  nqqz.assign(n+1,vector<ll>(20,inf));
  for (int i=n;i>=1;i--)
  {
    for (int j=0;j<20;j++)
    {
      if(j==0)
      {
        if(max(mn[i].first,mn[i].second)!=0)
        {
          nqqz[i][j]=max(mn[i].first,mn[i].second);
        }
      }
      else
      {
      if(max(mn[i].first,mn[i].second)!=0)
        {
          ll x=nqqz[i][j-1];
          if(x!=inf)
          {
            nqqz[i][j]=nqqz[x][j-1];
          }
        }
      }
    }
  }
}
int minimum_jumps(int A, int B, int C, int D) {

  if(mn[h[C]].first!=0 && ind[mn[h[C]].first] >= B) return -1;
  ll indd=A;
  if(mn[h[C]].first!=0)
  {
    indd=max(ind[mn[h[C]].first]+1,(ll)A);
  }
  ll cur=query(0,0,n-1,indd,B);
  ll ans=0;
  for (int j=19;j>=0;j--)
  {
    if(nqqz[cur][j]!=inf && nqqz[cur][j]<=h[C])
    {
      cur=nqqz[cur][j];
      ans+=1LL<<j;
    }
  }
  return limn[cur]-limn[h[C]]+ans;
}

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