Submission #988318

#	Time	Username	Problem	Language	Result	Execution time	Memory
988318		duckindog	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	100 / 100	562 ms	4308 KiB

skyscraper

#include <bits/stdc++.h>

using namespace std;

const int N = 30'000 + 10;
int n, m;
int b[N], p[N];
vector<int> power[N];
int f[N];

int32_t main() { 
	cin.tie(0)->sync_with_stdio(0);

	cin >> n >> m;
	for (int i = 0; i < m; ++i) cin >> b[i] >> p[i];

	for (int i = 0; i < m; ++i) power[b[i]].push_back(p[i]);

	memset(f, 63, sizeof f);
	using pii = pair<int, int>;
	
	priority_queue<pii, vector<pii>, greater<>> q;
	q.push({f[b[0]] = 0, b[0]});

	while (q.size()) { 
		auto [d, u] = q.top(); q.pop();
		if (d != f[u]) continue;
		for (const auto& pw : power[u]) {
			{
				int w = d;
				for (int v = u + pw; v < n; v += pw) if (f[v] > ++w) q.push({f[v] = w, v});
			}
			{
				int w = d;
				for (int v = u - pw; v >= 0; v -= pw) if (f[v] > ++w) q.push({f[v] = w, v});
			}
		}
	}
	
	cout << (f[b[1]] < f[n] ? f[b[1]] : -1) << "\n";
}

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