oj.uz

Submission #831180

# Submission time Handle Problem Language Result Execution time Memory
831180 2023-08-19T21:09:34 Z PurpleCrayon Sky Walking (IOI19_walk) C++17
33 / 100
 253 ms 49300 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) {
			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

			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] << 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

# Verdict Execution time Memory Grader output
1 Correct 10 ms 19028 KB Output is correct
2 Correct 12 ms 19156 KB Output is correct
3 Incorrect 10 ms 19028 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #2
0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 19016 KB Output is correct
2 Correct 11 ms 19028 KB Output is correct
3 Incorrect 129 ms 42900 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 59 ms 29508 KB Output is correct
2 Correct 144 ms 42552 KB Output is correct
3 Correct 161 ms 43152 KB Output is correct
4 Correct 182 ms 45720 KB Output is correct
5 Correct 241 ms 48932 KB Output is correct
6 Correct 227 ms 48044 KB Output is correct
7 Correct 86 ms 33536 KB Output is correct
8 Correct 96 ms 35064 KB Output is correct
9 Correct 213 ms 48812 KB Output is correct
10 Correct 153 ms 42924 KB Output is correct
11 Correct 18 ms 19800 KB Output is correct

Subtask #4
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 59 ms 29508 KB Output is correct
2 Correct 144 ms 42552 KB Output is correct
3 Correct 161 ms 43152 KB Output is correct
4 Correct 182 ms 45720 KB Output is correct
5 Correct 241 ms 48932 KB Output is correct
6 Correct 227 ms 48044 KB Output is correct
7 Correct 86 ms 33536 KB Output is correct
8 Correct 96 ms 35064 KB Output is correct
9 Correct 213 ms 48812 KB Output is correct
10 Correct 153 ms 42924 KB Output is correct
11 Correct 18 ms 19800 KB Output is correct
12 Correct 151 ms 43164 KB Output is correct
13 Correct 157 ms 45592 KB Output is correct
14 Correct 253 ms 48980 KB Output is correct
15 Correct 139 ms 38432 KB Output is correct
16 Correct 166 ms 47388 KB Output is correct
17 Correct 152 ms 43036 KB Output is correct
18 Correct 154 ms 38392 KB Output is correct
19 Correct 161 ms 48364 KB Output is correct
20 Correct 96 ms 33956 KB Output is correct
21 Correct 28 ms 20924 KB Output is correct
22 Correct 120 ms 40708 KB Output is correct
23 Correct 124 ms 40476 KB Output is correct
24 Correct 107 ms 36732 KB Output is correct
25 Correct 105 ms 39252 KB Output is correct
26 Correct 90 ms 33824 KB Output is correct
27 Correct 242 ms 49300 KB Output is correct
28 Correct 136 ms 45468 KB Output is correct
29 Correct 217 ms 47800 KB Output is correct
30 Correct 87 ms 33456 KB Output is correct
31 Correct 221 ms 48700 KB Output is correct
32 Correct 115 ms 39136 KB Output is correct
33 Correct 115 ms 38664 KB Output is correct
34 Correct 134 ms 42744 KB Output is correct
35 Correct 119 ms 39432 KB Output is correct
36 Correct 104 ms 37840 KB Output is correct
37 Correct 94 ms 35508 KB Output is correct
38 Correct 93 ms 35128 KB Output is correct
39 Correct 141 ms 43804 KB Output is correct
40 Correct 103 ms 35876 KB Output is correct
41 Correct 94 ms 36612 KB Output is correct

Subtask #5
0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 19028 KB Output is correct
2 Correct 12 ms 19156 KB Output is correct
3 Incorrect 10 ms 19028 KB Output isn't correct
4 Halted 0 ms 0 KB -