Submission #527825

#	Time	Username	Problem	Language	Result	Execution time	Memory
527825		Jasiekstrz	Railway Trip 2 (JOI22_ho_t4)	C++17	100 / 100	375 ms	66920 KiB

Main

#include<bits/stdc++.h>
#define fi first
#define se second
using namespace std;
const int N=1e5;
const int L=20;
const int P=(1<<17);
struct Seg
{
	int l,r;
};
Seg operator+(Seg a,Seg b)
{
	return {min(a.l,b.l),max(a.r,b.r)};
}
vector<int> ev[N+10];
multiset<int> ms;
Seg jmp[N+10][L+2];
int pot;
Seg tr[L+2][2*P+10];
void buildtr(int n,int l)
{
	for(int i=1;i<=n;i++)
		tr[l][pot+i-1]=jmp[i][l];
	for(int i=pot-1;i>0;i--)
		tr[l][i]=tr[l][2*i]+tr[l][2*i+1];
	return;
}
Seg read(int it,int l,int r)
{
	Seg ans={N+1,0};
	for(l+=pot-1,r+=pot-1;l<=r;l/=2,r/=2)
	{
		if(l%2==1)
			ans=ans+tr[it][l++];
		if(r%2==0)
			ans=ans+tr[it][r--];
	}
	return ans;
}
int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);
	int n,k,m,q;
	cin>>n>>k>>m;
	for(int i=1;i<=m;i++)
	{
		int a,b;
		cin>>a>>b;
		if(a<b)
		{
			ev[a].push_back(b);
			ev[min(a+k,b+1)].push_back(-b);
		}
		else
		{
			ev[max(a-k+1,b)].push_back(b);
			ev[a+1].push_back(-b);
		}
	}
	for(int i=1;i<=n;i++)
	{
		for(auto v:ev[i])
		{
			if(v>0)
				ms.insert(v);
			else
				ms.erase(ms.find(-v));
		}
		if(ms.empty())
			jmp[i][0]={i,i};
		else
			jmp[i][0]={min(i,*ms.begin()),max(i,*prev(ms.end()))};
		//cerr<<i<<": "<<jmp[i][0].l<<" "<<jmp[i][0].r<<"\n";
	}
	for(pot=1;pot<n;pot*=2);
	buildtr(n,0);
	for(int l=1;l<=L;l++)
	{
		for(int i=1;i<=n;i++)
			jmp[i][l]=read(l-1,jmp[i][l-1].l,jmp[i][l-1].r);
		buildtr(n,l);
	}
	cin>>q;
	while(q--)
	{
		int a,b;
		cin>>a>>b;
		if(a==b)
		{
			cout<<"0\n";
			return 0;
		}
		Seg s={a,a};
		if(b<jmp[a][L].l || jmp[a][L].r<b)
		{
			cout<<"-1\n";
			continue;
		}
		int ans=0;
		for(int l=L;l>=0;l--)
		{
			Seg tmp=read(l,s.l,s.r);
			if(b<tmp.l || tmp.r<b)
			{
				s=tmp;
				ans+=(1<<l);
			}
		}
		cout<<ans+1<<"\n";
	}
	return 0;
}

• Subtask 1: 8 / 8
• Subtask 2: 8 / 8
• Subtask 3: 11 / 11
• Subtask 4: 25 / 25
• Subtask 5: 35 / 35
• Subtask 6: 13 / 13