Submission #882481

#	Time	Username	Problem	Language	Result	Execution time	Memory
882481		vjudge1	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	10 / 100	2 ms	2664 KiB

skyscraper

#pragma GCC optimize("Ofast,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,sse4.2")
#include <bits/stdc++.h>
using namespace std;

#define int int64_t
const int MAXM = 3e5+5;

int n, p[MAXM], B[MAXM], m;
struct quad {
	int first, second, third, fourth;
	quad() : first(0), second(0), third(0), fourth(0) {}
	quad(int a, int b, int c, int d) :first(a), second(b), third(c), fourth(d) {}
	inline bool operator< (quad other) const {
		if(other.first != this->first) return this->first < other.first;
		if(other.second != this->second) return this->second < other.second;
		if(other.third != this->third) return this->third < other.third;
		return this->fourth < other.fourth;
	}
	inline bool operator> (quad other) const {
		if(other.first != this->first) return this->first > other.first;
		if(other.second != this->second) return this->second > other.second;
		if(other.third != this->third) return this->third > other.third;
		return this->fourth > other.fourth;
	}
};

signed main() {
	cin.tie(0)->sync_with_stdio(0);
	cin >> n >> m;
	for(int i = 0; i < m; i++) cin >> B[i] >> p[i];
	vector<int> a(n, INT64_MAX);
	vector<vector<int>> b(n);
	priority_queue<quad, vector<quad>, greater<quad>> pq;
	pq.push({0, B[0], p[0], 3});
	for(auto x:b[B[0]]) if(x!=0) pq.push({0, B[0], p[x], 3});
	a[B[0]] = 0ll;
	for(int i = 0; i < m; i++) b[B[i]].push_back(i);
	while(!pq.empty()) {
		auto cur = pq.top(); pq.pop();
		if(a[cur.second] == INT64_MAX) {
			for(auto x:b[cur.second]) if(p[x] != cur.third)pq.push({cur.first, cur.second, p[x], 3});
		}
		a[cur.second] = min(a[cur.second], cur.first);
		if(cur.second >= cur.third && cur.fourth != 2)
			pq.push({cur.first + 1, cur.second - cur.third, cur.third, 1});
		if(cur.second < n - cur.third && cur.fourth != 1)
			pq.push({cur.first + 1, cur.second + cur.third, cur.third, 2});
	}
	cout << (a[B[1]] == INT64_MAX ? -1 : a[B[1]]) << '\n';
}

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