Submission #46582

#	Time	Username	Problem	Language	Result	Execution time	Memory
46582		aome	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	100 / 100	852 ms	38268 KiB

skyscraper

#include <bits/stdc++.h>

using namespace std;

const int N = 30005;
const int B = 205;
const int INF = 0x3f3f3f3f;

int n, m;
int b[N], p[N];
int f[N][B];
vector<int> vec[N];

struct State {
	int w, x, y;

	State (int w, int x, int y) : w(w), x(x), y(y) {}

	bool operator < (const State& rhs) const {
		return w > rhs.w;
	}
};

int solve() {
	memset(f, INF, sizeof f);
	priority_queue<State> pq;
	pq.push(State(0, b[0], 0));
	f[b[0]][0] = 0;
	while (pq.size()) {
		State u = pq.top(); pq.pop();
		if (u.w != f[u.x][u.y]) continue;
		if (u.x == b[1]) return u.w;
		if (u.y) {
			if (f[u.x][0] > u.w) {
				f[u.x][0] = u.w, pq.push(State(u.w, u.x, 0));
			}
			if (u.x + u.y < n && f[u.x + u.y][u.y] > u.w + 1) {
				f[u.x + u.y][u.y] = u.w + 1, pq.push(State(u.w + 1, u.x + u.y, u.y));
			}
			if (u.x - u.y >= 0 && f[u.x - u.y][u.y] > u.w + 1) {
				f[u.x - u.y][u.y] = u.w + 1, pq.push(State(u.w + 1, u.x - u.y, u.y));
			}
		}
		else {
			for (auto i : vec[u.x]) {
				if (p[i] >= B) {
					for (int j = u.x % p[i]; j < n; j += p[i]) {
						if (f[j][0] > u.w + abs(u.x - j) / p[i]) {
							f[j][0] = u.w + abs(u.x - j) / p[i], pq.push(State(f[j][0], j, 0));
						}
					}
				}
				else {
					if (f[u.x][p[i]] > u.w) {
						f[u.x][p[i]] = u.w, pq.push(State(u.w, u.x, p[i]));
					}
				}
			}
		}
	}
	return -1;
}

int main() {
	ios::sync_with_stdio(false);
	cin >> n >> m;
	for (int i = 0; i < m; ++i) {
		cin >> b[i] >> p[i], vec[b[i]].push_back(i);
	}
	cout << solve();
}

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