Submission #341809

#	Time	Username	Problem	Language	Result	Execution time	Memory
341809		egod1537	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	57 / 100	1085 ms	36332 KiB

skyscraper

#include <bits/stdc++.h>

using namespace std;

const int INF = 0x3f3f3f3f;

typedef pair<int, int> pi;
#define to first
#define cost second
#define pos first
#define range second

struct Q {
	int pos, cost;
};
bool operator<(const Q& a, const Q& b) {
	return a.cost > b.cost;
}

set<pi> V[30001];
set<int> vitP[30001];
int dst[30001];

int main() {
	ios::sync_with_stdio(0);
	cin.tie(0), cout.tie(0);

	memset(dst, INF, sizeof(dst));

	int n, m; cin >> n >> m;
	vector<pi> doge(m);
	vector<int> posdoge(n + 1, -1);

	int s = 0, e = 0;
	for (int i = 0; i < m; i++) {
		cin >> doge[i].pos >> doge[i].range;
		if (i == 0) s = doge[i].pos;
		if (i == 1) e = doge[i].pos;
		vitP[doge[i].pos].insert(doge[i].range);
	}

	for (int i = 0; i < m; i++) {
		pi& now = doge[i];
		for (int j = now.pos + now.range; j < n; j += now.range) {
			if (vitP[j].size() == 0) continue;
			int dst = j - now.pos;
			V[now.pos].insert({ j, dst / now.range });
			if (vitP[j].find(now.range) != vitP[j].end()) break;
		}
		for (int j = now.pos - now.range; j >= 0; j -= now.range) {
			if (vitP[j].size() == 0) continue;
			int dst = now.pos - j;
			V[now.pos].insert({ j, dst / now.range });
			if (vitP[j].find(now.range) != vitP[j].end()) break;
		}
	}

	priority_queue<Q> pq;
	pq.push({ s, 0 });
	while (!pq.empty()) {
		Q top = pq.top(); pq.pop();

		if (top.pos == e) {
			cout << top.cost;
			return 0;
		}

		for (pi w : V[top.pos]) {
			if (dst[w.to] > top.cost + w.cost) {
				dst[w.to] = top.cost + w.cost;
				pq.push({ w.to, dst[w.to] });
			}
		}
	}

	cout << -1;

	return 0;
}

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