Submission #919112

#	Time	Username	Problem	Language	Result	Execution time	Memory
919112		vjudge1	Deda (COCI17_deda)	C++17	0 / 140	24 ms	26820 KiB

deda

#include <bits/stdc++.h>
using i64 = long long;

struct DSU {
	int n;
	std::vector<int> par;
	DSU(int _n) : n(_n) {
		par.resize(n);
		std::iota(par.begin(), par.end(), 0);
	}

	int get(int x) {
		if(par[x] == x) {
			return x;
		}

		return par[x] = get(par[x]);
	}

	bool same(int a, int b) {
		return get(a) == get(b);
	}

	bool unite(int u, int v) {
		if(same(u, v)) {
			return false;
		}

		u = get(u);
		v = get(v);
		par[u] = v;

		return true;
	}
};

double solve(int N, int M, int K, int H, std::vector<int> x, std::vector<int> y, std::vector<int> c, std::vector<int> arr) {
	DSU dsu(N);
	std::vector<std::pair<int, int>> adj[N];
	for(int i = 0; i < M; i++) {
		dsu.unite(x[i], y[i]);
		adj[x[i]].emplace_back(y[i], c[i]);
		adj[y[i]].emplace_back(x[i], c[i]);
	}

	if(!dsu.same(0, H)) {
		return -1;
	}

	K = std::min(100, K);

	std::vector<double> pw(K + 1, 1);
	for(int i = 1; i <= K; i++) {
		pw[i] = pw[i - 1] / 2;
	}

	using T = std::tuple<int, int, int>;
	std::priority_queue<T, std::vector<T>, std::greater<T>> pq;
	pq.emplace(0, H, 0);

	std::vector dist(N, std::vector<double> (K + 1, -1));
	while(!pq.empty()) {
		auto [cost, node, bound] = pq.top();
		pq.pop();
		if(dist[node][bound] != -1) {
			continue;
		}

		dist[node][bound] = cost;
		
		if(arr[node] == 0) {
			return cost;
		} else if(node == 0) {
			return cost;
		}

		for(auto [child, w] : adj[node]) {
			pq.emplace(cost + w * pw[bound], child, bound);
			if(arr[child] == 2) {
				pq.emplace(cost + w * pw[bound + 1], child, bound + 1);
			}
		}
	}

	return -1;
}

void solve() {
	int N, M, K;
	std::cin >> N >> M >> K;

	int H;
	std::cin >> H;

	std::vector<int> arr(N);
	for(int i = 0; i < N; i++) {
		std::cin >> arr[i];
	}

	std::vector<int> x(M), y(M), c(M);
	for(int i = 0; i < M; i++) {
		std::cin >> x[i] >> y[i] >> c[i];
	}

	std::cout << solve(N, M, K, H, x, y, c, arr);

	return;
}

signed main() {
    #ifdef LOCAL
        freopen("in.txt", "r", stdin);
        freopen("out.txt", "w", stdout);
    #endif

    std::ios_base::sync_with_stdio(false);
    std::cin.tie(NULL); std::cout.tie(NULL);

    int t = 1; //std::cin >> t;
    for(int i = 1; i <= t; i++) {
        solve();
    }

    return 0;
}

• Subtask 1: 0 / 140