oj.uz

답안 #831183

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
831183 2023-08-19T21:29:36 Z PurpleCrayon Sky Walking (IOI19_walk) C++17
33 / 100
 247 ms 49324 KB 
#include "walk.h"
#include <bits/stdc++.h>
using namespace std;

#define sz(v) int(v.size())
#define ar array
typedef long long ll;
const int N = 6e5+10;
const ll INF = 1e18+10;

template <class T>
using min_pq = priority_queue<T, vector<T>, greater<T>>;

int n, m;
vector<pair<int, ll>> adj[N];
ll dist[N], extra[N]; // extra cost for the nodes

void add_edge(int a, int b, ll w) {
	// cerr << "add: " << a << ' ' << b << ' ' << w << endl;
	adj[a].emplace_back(b, w);
	adj[b].emplace_back(a, w);
}

void dijkstra(int S) {
	fill(dist, dist + N, INF);
	for (int a = 0; a < N; a++) {
		for (auto& [b, w] : adj[a]) {
			w += extra[b];
		}
	}

	min_pq<pair<ll, int>> pq;
	pq.push({dist[S] = 0, S});

	while (!pq.empty()) {
		auto [d_c, c] = pq.top(); pq.pop();
		if (dist[c] != d_c) continue;
		for (auto [nxt, w] : adj[c]) {
			if (dist[nxt] > dist[c] + w) {
				dist[nxt] = dist[c] + w;
				pq.push({dist[nxt], nxt});
			}
		}
	}
}

long long min_distance(vector<int> x, vector<int> h, vector<int> l, vector<int> r, vector<int> y, int s, int g) {
	n = sz(x), m = sz(l);

	
	vector<int> nl, nr, ny;
	for (int i = 0; i < m; i++) {
		if (l[i] < s && r[i] > s) {
			bool has = 0;
			for (int j = s; j <= g; j++) if (h[j] >= y[i]) {
				has = 1;
			}

			if (!has) {
				extra[sz(nl)] += x[s] - x[l[i]] + x[r[i]] - x[g];
				nl.push_back(l[i]);
				nr.push_back(r[i]);
				ny.push_back(y[i]);
				continue;
			}
		}

		if (l[i] < s && r[i] >= s) {
			int one = s-1;
			while (one >= l[i] && h[one] < y[i]) one--;
			int two = s;
			while (two <= r[i] && h[two] < y[i]) two++;

			// [l, one]
			// [one, two] -> extra of x[s] - x[one]
			// l[i] = two

			// cerr << "> " << one << ' ' << l[i] << ' ' << two << endl;
			if (l[i] < one) { nl.push_back(l[i]); nr.push_back(one); ny.push_back(y[i]); }
			if (one < two && two <= r[i]) {
				// cerr << "extra: " << sz(nl) << ' ' << x[s] - x[one] << endl;
				extra[sz(nl)] += x[s] - x[one];
				nl.push_back(one); nr.push_back(two); ny.push_back(y[i]);
			}

			l[i] = two;
		}

		if (r[i] > g && l[i] <= g) {
			int one = g+1;
			while (one <= r[i] && h[one] < y[i]) one++;
			int two = g;
			while (two >= l[i] && h[two] < y[i]) two--;

			// [one, r]
			// [two, one] -> extra of x[one] - x[g]
			// r[i] = two

			if (one < r[i]) { nl.push_back(one); nr.push_back(r[i]); ny.push_back(y[i]); }
			if (two < one && two >= l[i]) {
				extra[sz(nl)] += x[one] - x[g];
				nl.push_back(two), nr.push_back(one), ny.push_back(y[i]);
			}

			r[i] = two;
		}

		if (l[i] < r[i]) {
			nl.push_back(l[i]);
			nr.push_back(r[i]);
			ny.push_back(y[i]);
		}
	}

	// cout << sz(l) << ' ' << sz(r) << ' ' << sz(y) << endl;
	swap(l, nl); swap(r, nr); swap(y, ny);
	// cout << sz(l) << ' ' << sz(r) << ' ' << sz(y) << endl;
	m = sz(l);
	// for (int i = 0; i < m; i++) {
	// 	cerr << l[i] << ' ' << r[i] << ' ' << y[i] << ' ' << extra[i] << endl;
	// }
	// s = 0;

	auto build = [&]() {
		vector<vector<int>> ev(n);
		for (int i = 0; i < m; i++) {
			ev[l[i]].push_back(i);
			ev[r[i]].push_back(i);
		}

		vector<bool> on(m);
		set<pair<int, int>> s;
		for (int i = 0; i < n; i++) {
			for (int x : ev[i]) if (!on[x]) {
				auto me = s.insert({y[x], x}).first;

				if (y[x] <= h[i]) {
					auto it = next(me);
					if (it != s.end() && it->first <= h[i]) {
						// cerr << "h1\n";
						add_edge(x, it->second, it->first - y[x]);
					}
				}

				if (y[x] <= h[i]) {
					if (me != s.begin()) {
						auto it = prev(me);
						// cerr << "h2\n";
						add_edge(x, it->second, y[x] - it->first);
					}
				}
			}

			for (int x : ev[i]) if (on[x]) {
				auto me = s.find({y[x], x});
				if (y[x] <= h[i]) {
					auto it = next(me);
					if (it != s.end() && it->first <= h[i]) {
						// cerr << "h3\n";
						add_edge(x, it->second, it->first - y[x]);
					}
				}

				if (y[x] <= h[i]) {
					if (me != s.begin()) {
						// cerr << "h3\n";
						auto it = prev(me);
						add_edge(x, it->second, y[x] - it->first);
					}
				}

				s.erase(me);
			}

			for (int x : ev[i]) on[x] = !on[x];
		}
	};

	build();
	int S = m;
	for (int i = 0; i < m; i++) {
		// cerr << "> " << l[i] << ' ' << s << ' ' << r[i] << ' ' << y[i] << ' ' << h[s] << endl;
		if (l[i] <= s && s <= r[i] && y[i] <= h[s]) {
			add_edge(S, i, y[i]);
		}
	}
	dijkstra(S);

	ll ans = INF;
	for (int i = 0; i < m; i++) {
		
		if (l[i] <= g && g <= r[i] && y[i] <= h[g]) {
			ans = min(ans, dist[i] + y[i]);
		}
	}
	// cerr << "base: " << ans << endl;

	// cerr << x[n-1] - x[0] << ' ' << ans << endl;
	if (ans == INF) return -1;
	return ans + x[g] - x[s];
}

Subtask #1
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 11 ms 19092 KB Output is correct
2 Correct 10 ms 19028 KB Output is correct
3 Incorrect 12 ms 19028 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #2
0 / 14.0

# 결과 실행 시간 메모리 Grader output
1 Correct 10 ms 19084 KB Output is correct
2 Correct 10 ms 19068 KB Output is correct
3 Incorrect 128 ms 42888 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #3
15.0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 57 ms 29536 KB Output is correct
2 Correct 143 ms 42540 KB Output is correct
3 Correct 158 ms 43224 KB Output is correct
4 Correct 184 ms 45612 KB Output is correct
5 Correct 247 ms 48948 KB Output is correct
6 Correct 219 ms 48024 KB Output is correct
7 Correct 85 ms 33576 KB Output is correct
8 Correct 100 ms 35048 KB Output is correct
9 Correct 215 ms 48740 KB Output is correct
10 Correct 139 ms 42792 KB Output is correct
11 Correct 20 ms 19904 KB Output is correct

Subtask #4
18.0 / 18.0

# 결과 실행 시간 메모리 Grader output
1 Correct 57 ms 29536 KB Output is correct
2 Correct 143 ms 42540 KB Output is correct
3 Correct 158 ms 43224 KB Output is correct
4 Correct 184 ms 45612 KB Output is correct
5 Correct 247 ms 48948 KB Output is correct
6 Correct 219 ms 48024 KB Output is correct
7 Correct 85 ms 33576 KB Output is correct
8 Correct 100 ms 35048 KB Output is correct
9 Correct 215 ms 48740 KB Output is correct
10 Correct 139 ms 42792 KB Output is correct
11 Correct 20 ms 19904 KB Output is correct
12 Correct 149 ms 43172 KB Output is correct
13 Correct 159 ms 45596 KB Output is correct
14 Correct 245 ms 48928 KB Output is correct
15 Correct 150 ms 38500 KB Output is correct
16 Correct 160 ms 47412 KB Output is correct
17 Correct 150 ms 43084 KB Output is correct
18 Correct 139 ms 38432 KB Output is correct
19 Correct 167 ms 48564 KB Output is correct
20 Correct 94 ms 33964 KB Output is correct
21 Correct 28 ms 20912 KB Output is correct
22 Correct 124 ms 40680 KB Output is correct
23 Correct 112 ms 40488 KB Output is correct
24 Correct 99 ms 36764 KB Output is correct
25 Correct 103 ms 39316 KB Output is correct
26 Correct 93 ms 33840 KB Output is correct
27 Correct 240 ms 49324 KB Output is correct
28 Correct 136 ms 45488 KB Output is correct
29 Correct 211 ms 47800 KB Output is correct
30 Correct 88 ms 33452 KB Output is correct
31 Correct 223 ms 48688 KB Output is correct
32 Correct 120 ms 39228 KB Output is correct
33 Correct 113 ms 38556 KB Output is correct
34 Correct 130 ms 42668 KB Output is correct
35 Correct 120 ms 39356 KB Output is correct
36 Correct 102 ms 37832 KB Output is correct
37 Correct 100 ms 35640 KB Output is correct
38 Correct 92 ms 35108 KB Output is correct
39 Correct 146 ms 43836 KB Output is correct
40 Correct 98 ms 35864 KB Output is correct
41 Correct 95 ms 36720 KB Output is correct

Subtask #5
0 / 43.0

# 결과 실행 시간 메모리 Grader output
1 Correct 11 ms 19092 KB Output is correct
2 Correct 10 ms 19028 KB Output is correct
3 Incorrect 12 ms 19028 KB Output isn't correct
4 Halted 0 ms 0 KB -