oj.uz

Submission #831172

# Submission time Handle Problem Language Result Execution time Memory
831172 2023-08-19T20:52:47 Z PurpleCrayon Sky Walking (IOI19_walk) C++17
33 / 100
 264 ms 49296 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) {
	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) {
			int one = s;
			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

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

			nl.push_back(one); nr.push_back(r[i]); ny.push_back(y[i]);
			if (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);

	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]) {
						add_edge(x, it->second, it->first - y[x]);
					}
				}

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

				if (y[x] <= h[i]) {
					if (me != s.begin()) {
						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++) {
		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

# Verdict Execution time Memory Grader output
1 Incorrect 10 ms 19028 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
0 / 14.0

# Verdict Execution time Memory Grader output
1 Incorrect 10 ms 19028 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 60 ms 29548 KB Output is correct
2 Correct 145 ms 42508 KB Output is correct
3 Correct 150 ms 43160 KB Output is correct
4 Correct 183 ms 45720 KB Output is correct
5 Correct 264 ms 49012 KB Output is correct
6 Correct 214 ms 48016 KB Output is correct
7 Correct 86 ms 33608 KB Output is correct
8 Correct 96 ms 35108 KB Output is correct
9 Correct 226 ms 48792 KB Output is correct
10 Correct 143 ms 42772 KB Output is correct
11 Correct 18 ms 19772 KB Output is correct

Subtask #4
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 60 ms 29548 KB Output is correct
2 Correct 145 ms 42508 KB Output is correct
3 Correct 150 ms 43160 KB Output is correct
4 Correct 183 ms 45720 KB Output is correct
5 Correct 264 ms 49012 KB Output is correct
6 Correct 214 ms 48016 KB Output is correct
7 Correct 86 ms 33608 KB Output is correct
8 Correct 96 ms 35108 KB Output is correct
9 Correct 226 ms 48792 KB Output is correct
10 Correct 143 ms 42772 KB Output is correct
11 Correct 18 ms 19772 KB Output is correct
12 Correct 150 ms 43140 KB Output is correct
13 Correct 162 ms 45612 KB Output is correct
14 Correct 248 ms 48920 KB Output is correct
15 Correct 143 ms 38420 KB Output is correct
16 Correct 163 ms 47400 KB Output is correct
17 Correct 157 ms 43036 KB Output is correct
18 Correct 140 ms 38424 KB Output is correct
19 Correct 162 ms 48384 KB Output is correct
20 Correct 94 ms 33976 KB Output is correct
21 Correct 28 ms 20908 KB Output is correct
22 Correct 130 ms 40720 KB Output is correct
23 Correct 110 ms 40428 KB Output is correct
24 Correct 103 ms 36796 KB Output is correct
25 Correct 103 ms 39288 KB Output is correct
26 Correct 89 ms 33796 KB Output is correct
27 Correct 240 ms 49296 KB Output is correct
28 Correct 138 ms 45480 KB Output is correct
29 Correct 212 ms 47888 KB Output is correct
30 Correct 91 ms 33700 KB Output is correct
31 Correct 218 ms 48700 KB Output is correct
32 Correct 120 ms 39136 KB Output is correct
33 Correct 119 ms 38552 KB Output is correct
34 Correct 131 ms 42728 KB Output is correct
35 Correct 118 ms 39312 KB Output is correct
36 Correct 104 ms 37840 KB Output is correct
37 Correct 95 ms 35568 KB Output is correct
38 Correct 92 ms 35096 KB Output is correct
39 Correct 155 ms 43924 KB Output is correct
40 Correct 99 ms 35912 KB Output is correct
41 Correct 95 ms 36688 KB Output is correct

Subtask #5
0 / 43.0

# Verdict Execution time Memory Grader output
1 Incorrect 10 ms 19028 KB Output isn't correct
2 Halted 0 ms 0 KB -