Submission #297382

#	Time	Username	Problem	Language	Result	Execution time	Memory
297382		AaronNaidu	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	10 / 100	3 ms	2816 KiB

skyscraper

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;

int n, m, b, p;
vector<int> doges[50000];
vector<pair<int, int> > graph[50000];
int powers[50000];
int positions[50000];
priority_queue<pair<int, int> > q;
int dists[50000];
bool visited[50000];

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    cin >> n >> m;
    for (int i = 0; i < m; i++)
    {
        cin >> b >> p;
        powers[i] = p;
        positions[i] = b;
        doges[b].push_back(i);
        dists[i] = 1000000000;
    }
    for (int i = 0; i < m; i++)
    {
        int jumpCount = -1;
        for (int j = positions[i]; j < n; j+=powers[i])
        {
            jumpCount++;
            for (auto k : doges[j])
            {
                graph[i].push_back({k, jumpCount});
            }
        }
        jumpCount = 0;
        for (int j = positions[i]-powers[i]; j >= 0; j-=powers[i])
        {
            jumpCount++;
            for (auto k : doges[j])
            {
                graph[i].push_back({k, jumpCount});
            }
        }
    }
    q.push({0, 0});
    dists[0] = 0;
    while (!q.empty()) 
    {
        int x = q.top().second;
        if (x == 1)
        {
            int ans = -dists[1];
            cout << ans << "\n";
            return 0;
        }
        q.pop();
        if (visited[x])
        {
            continue;
        }
        visited[x] = true;
        for (auto i : graph[x])
        {
            if (!visited[i.first] and dists[x] - i.second < dists[i.first])
            {
                dists[i.first] = dists[x] - i.second;
                q.push({-dists[i.first], i.first});
            }
        }
    }
    cout << "-1\n";
}

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