oj.uz

Submission #276569

# Submission time Handle Problem Language Result Execution time Memory
276569 2020-08-20T13:55:51 Z islingr Olympic Bus (JOI20_ho_t4) C++17
11 / 100
 46 ms 2424 KB 
#include <bits/stdc++.h>
#include <ext/pb_ds/priority_queue.hpp>
using namespace std;

#define rep(i, a, b) for (auto i = (a); i < (b); ++i)
#define all(x...) begin(x), end(x)

using ll = long long;

template<class T> bool ckmin(T &a, const T &b) { return a > b ? a = b, 1 : 0; }
template<class T> bool ckmax(T &a, const T &b) { return a < b ? a = b, 1 : 0; }

const int N = 1 << 9, M = 1 << 16;
const ll inf = 1e18;

int n;
ll d[N][N];
int a[M], b[M], w[M], c[M];
vector<int> g[N];

using pq_t = __gnu_pbds::priority_queue<pair<ll, int>, greater<>>;
pq_t::point_iterator it[N];

ll dij(int s, int t) {
	pq_t pq;
	rep(u, 0, n) if (u != s) it[u] = pq.push({inf, u});
	it[s] = pq.push({0, s});
	while (!pq.empty()) {
		 ll dist; int u;
		tie(dist, u) = pq.top();
		pq.pop(); it[u] = nullptr;
		if (u == t) return dist;
		for (int e : g[u]) {
			int v = b[e];
			if (it[v] != nullptr) {
				dist += w[e];
				if (dist < it[v]->first) pq.modify(it[v], {dist, v});
				dist -= w[e];
			}
		}
	}
	return inf;
}

signed main() {
	cin.tie(nullptr)->sync_with_stdio(false);

	int m; cin >> n >> m;
	rep(u, 0, n) rep(v, 0, n) d[u][v] = inf;
	rep(u, 0, n) d[u][u] = 0;
	rep(e, 0, m) {
		cin >> a[e] >> b[e] >> w[e] >> c[e], --a[e], --b[e];
		ckmin(d[a[e]][b[e]], ll(w[e]));
		g[a[e]].push_back(e);
	}

	rep(w, 0, n) rep(u, 0, n) rep(v, 0, n) ckmin(d[u][v], d[u][w] + d[w][v]);

	int s = 0, t = n - 1;
	ll ans = d[s][t] + d[t][s];
	rep(e, 0, m) {
		ll to = min(d[s][t], d[s][b[e]] + w[e] + d[a[e]][t]);
		ll fr = min(d[t][s], d[t][b[e]] + w[e] + d[a[e]][s]);
		if (ckmin(ans, c[e] + to + fr)) {
			g[a[e]].erase(find(all(g[a[e]]), e));
			swap(a[e], b[e]);
			g[a[e]].push_back(e);
			ckmin(ans, c[e] + dij(s, t) + dij(t, s));
			g[a[e]].pop_back();
			swap(a[e], b[e]);
			g[a[e]].push_back(e);
		}
	}

	cout << (ans < inf ? ans : -1);
}

Subtask #1
0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 1152 KB Output is correct
2 Correct 14 ms 1184 KB Output is correct
3 Correct 12 ms 1152 KB Output is correct
4 Correct 12 ms 1152 KB Output is correct
5 Correct 1 ms 512 KB Output is correct
6 Correct 10 ms 1152 KB Output is correct
7 Incorrect 1 ms 384 KB Output isn't correct
8 Halted 0 ms 0 KB -

Subtask #2
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 37 ms 2304 KB Output is correct
2 Correct 46 ms 2296 KB Output is correct
3 Correct 35 ms 2296 KB Output is correct
4 Correct 18 ms 1280 KB Output is correct
5 Correct 11 ms 1152 KB Output is correct
6 Correct 10 ms 1152 KB Output is correct
7 Correct 10 ms 1152 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 41 ms 2304 KB Output is correct
10 Correct 36 ms 2424 KB Output is correct
11 Correct 33 ms 2304 KB Output is correct
12 Correct 40 ms 2296 KB Output is correct
13 Correct 39 ms 2296 KB Output is correct
14 Correct 34 ms 2304 KB Output is correct

Subtask #3
0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 1152 KB Output is correct
2 Correct 10 ms 1152 KB Output is correct
3 Correct 24 ms 2048 KB Output is correct
4 Correct 10 ms 1152 KB Output is correct
5 Correct 30 ms 2376 KB Output is correct
6 Incorrect 0 ms 384 KB Output isn't correct
7 Halted 0 ms 0 KB -

Subtask #4
0 / 63.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 1152 KB Output is correct
2 Correct 14 ms 1184 KB Output is correct
3 Correct 12 ms 1152 KB Output is correct
4 Correct 12 ms 1152 KB Output is correct
5 Correct 1 ms 512 KB Output is correct
6 Correct 10 ms 1152 KB Output is correct
7 Incorrect 1 ms 384 KB Output isn't correct
8 Halted 0 ms 0 KB -