Submission #695131

#	Time	Username	Problem	Language	Result	Execution time	Memory
695131		Cyber_Wolf	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	10 / 100	33 ms	22684 KiB

skyscraper

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

#define lg long long
#define fastio ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
//Jakarta Skyscraper

const lg N  = 300005;

lg dist[N], in_queue[N];
vector<set<pair<lg, lg>>> adj(N);
vector<lg> b(N), p(N);

void dijkstra(lg src)
{
	priority_queue<array<lg, 2>> pq;
	pq.push({0, src});
	in_queue[src] = 1;
	memset(dist, 0x3f, sizeof(dist));
	dist[src] = 0;
	while(pq.size())
	{
		lg x = pq.top()[1];
		in_queue[x] = 0;
		pq.pop();
		for(auto [it, c] : adj[x])
		{
			if(dist[it] > dist[x]+c)
			{
				dist[it] = dist[x]+c;
				if(!in_queue[it])	pq.push({-dist[it], it});
				in_queue[it] = true;
			}
		}
	}
	return;
}


int main()
{
	fastio;
	lg n, m;
	cin >> n >> m;
	for(int i = 0; i < m; i++)
	{
		cin >> b[i] >> p[i];
	} 
	map<array<lg, 2>, lg> mp;
	for(int i = 0; i < m; i++)
	{
		lg x = b[i]+p[i], z = 1;
		while(x < n)
		{
			if(!mp.count({b[i], x}))
			{
				adj[b[i]].insert({x, z});	
				mp[{b[i], x}] = z;
			}
			else if(mp[{b[i], x}] > z)
			{
				adj[b[i]].insert({x, z});
				adj[b[i]].erase(adj[b[i]].find({x, z}));
				mp[{b[i], x}] = z;
			}
			z++;
			x += p[i];
		}
		x = b[i]-p[i];
		z = 1;
		while(x >= 0)
		{
			if(!mp.count({b[i], x}))
			{
				adj[b[i]].insert({x, z});	
				mp[{b[i], x}] = z;
			}
			else if(mp[{b[i], x}] > z)
			{
				adj[b[i]].insert({x, z});
				adj[b[i]].erase(adj[b[i]].find({x, z}));
				mp[{b[i], x}] = z;
			}
			z++;
			x -= p[i];
		}
	}
	dijkstra(b[0]);
	if(dist[b[1]] == dist[N-1])
	{
		cout << "-1\n";
		return 0;
	}
	cout << dist[b[1]] << '\n';

    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 0 / 12
• Subtask 3: 0 / 14
• Subtask 4: 0 / 21
• Subtask 5: 0 / 43