Submission #389984

#	Time	Username	Problem	Language	Result	Execution time	Memory
389984		thuanqvbn03	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	100 / 100	661 ms	4040 KiB

skyscraper

//Flower_On_Stone
#include <bits/stdc++.h>

using namespace std;

const int MAX_N = 30005;
const int INF = 1000000000;

int numSkycrepers, numDoge;
vector<int> doge[MAX_N];
int dist[MAX_N];
priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> pq;
int b[MAX_N], p[MAX_N];

void dijkstra(int x)
{
    for (int i = 0; i < numSkycrepers; i++)
    {
        dist[i] = INF;
    }
    dist[x] = 0;
    pq.push(make_pair(0, x));
    while (!pq.empty())
    {
        int node, w;
        tie(w, node) = pq.top();
        pq.pop();
        if (w != dist[node])
        {
            continue;
        }
        for (auto &p : doge[node])
        {
            for (int u = node + p, cnt = 1; u < numSkycrepers; u += p, cnt++)
            {
                if (w + cnt < dist[u])
                {
                    dist[u] = w + cnt;
                    pq.push(make_pair(w + cnt, u));
                }
            }
            for (int u = node - p, cnt = 1; u >= 0; u -= p, cnt++)
            {
                if (w + cnt < dist[u])
                {
                    dist[u] = w + cnt;
                    pq.push(make_pair(w + cnt, u));
                }
            }
        }
    }
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    cin >> numSkycrepers >> numDoge;
    for (int i = 0; i < numDoge; i++)
    {
        cin >> b[i] >> p[i];
        doge[b[i]].push_back(p[i]);
    }
    if (b[0] == b[1])
    {
        cout << 0;
        return 0;
    }
    for (int i = 0; i < numSkycrepers; i++)
    {
        sort(doge[i].begin(), doge[i].end(), greater<int>());
        doge[i].resize(distance(doge[i].begin(), unique(doge[i].begin(), doge[i].end())));
    }
    dijkstra(b[0]);
    cout << (dist[b[1]] == INF ? -1 : dist[b[1]]);
    return 0;
}

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