Submission #831186

# Submission time Handle Problem Language Result Execution time Memory
831186 2023-08-19T21:40:12 Z PurpleCrayon Sky Walking (IOI19_walk) C++17
33 / 100
263 ms 49312 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) {
				int one = s;
				int two = g;
				while (h[one] < y[i]) one--;
				while (h[two] < y[i]) two++;
				l[i] = one, r[i] = two;
				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];
}
# Verdict Execution time Memory Grader output
1 Correct 10 ms 19028 KB Output is correct
2 Correct 10 ms 19028 KB Output is correct
3 Incorrect 10 ms 19028 KB Output isn't correct
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 10 ms 19028 KB Output is correct
2 Correct 10 ms 19028 KB Output is correct
3 Incorrect 132 ms 42780 KB Output isn't correct
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 60 ms 29508 KB Output is correct
2 Correct 150 ms 42680 KB Output is correct
3 Correct 152 ms 43204 KB Output is correct
4 Correct 182 ms 45624 KB Output is correct
5 Correct 245 ms 48940 KB Output is correct
6 Correct 213 ms 47968 KB Output is correct
7 Correct 86 ms 33576 KB Output is correct
8 Correct 99 ms 35108 KB Output is correct
9 Correct 225 ms 48808 KB Output is correct
10 Correct 142 ms 42804 KB Output is correct
11 Correct 18 ms 19776 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 60 ms 29508 KB Output is correct
2 Correct 150 ms 42680 KB Output is correct
3 Correct 152 ms 43204 KB Output is correct
4 Correct 182 ms 45624 KB Output is correct
5 Correct 245 ms 48940 KB Output is correct
6 Correct 213 ms 47968 KB Output is correct
7 Correct 86 ms 33576 KB Output is correct
8 Correct 99 ms 35108 KB Output is correct
9 Correct 225 ms 48808 KB Output is correct
10 Correct 142 ms 42804 KB Output is correct
11 Correct 18 ms 19776 KB Output is correct
12 Correct 152 ms 43128 KB Output is correct
13 Correct 161 ms 45596 KB Output is correct
14 Correct 260 ms 48952 KB Output is correct
15 Correct 146 ms 38420 KB Output is correct
16 Correct 165 ms 47316 KB Output is correct
17 Correct 168 ms 43244 KB Output is correct
18 Correct 141 ms 38420 KB Output is correct
19 Correct 167 ms 48404 KB Output is correct
20 Correct 95 ms 33992 KB Output is correct
21 Correct 28 ms 20908 KB Output is correct
22 Correct 125 ms 40728 KB Output is correct
23 Correct 131 ms 40464 KB Output is correct
24 Correct 103 ms 36808 KB Output is correct
25 Correct 106 ms 39324 KB Output is correct
26 Correct 92 ms 33844 KB Output is correct
27 Correct 263 ms 49312 KB Output is correct
28 Correct 138 ms 45472 KB Output is correct
29 Correct 219 ms 47892 KB Output is correct
30 Correct 87 ms 33540 KB Output is correct
31 Correct 222 ms 48800 KB Output is correct
32 Correct 114 ms 39144 KB Output is correct
33 Correct 115 ms 38600 KB Output is correct
34 Correct 134 ms 42672 KB Output is correct
35 Correct 120 ms 39412 KB Output is correct
36 Correct 105 ms 37916 KB Output is correct
37 Correct 95 ms 35516 KB Output is correct
38 Correct 93 ms 35148 KB Output is correct
39 Correct 145 ms 44012 KB Output is correct
40 Correct 99 ms 35784 KB Output is correct
41 Correct 99 ms 36712 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 10 ms 19028 KB Output is correct
2 Correct 10 ms 19028 KB Output is correct
3 Incorrect 10 ms 19028 KB Output isn't correct
4 Halted 0 ms 0 KB -