Submission #510020

#	Time	Username	Problem	Language	Result	Execution time	Memory
510020		haxorman	Paths (BOI18_paths)	C++14	0 / 100	63 ms	16704 KiB

paths

#include <bits/stdc++.h>
using namespace std;

#define int long long

const int mxN = 3e5 + 7;
const int mxK = 39;

int n, m, k, color[mxN], dp[mxN][mxK];
vector<int> graph[mxN];
bool vis[mxN];

void dfs(int u, int mask, int cnt) {
	vis[u] = true;

	if (dp[u][mask]) {
		return;
	}

	if (cnt > 1) {
		dp[u][mask] = 1;
	}

	for (auto v : graph[u]) {
		if (!vis[v]) {
			if (!(mask & (1 << color[v]))) {
				dfs(v, mask & (1 << color[v]), cnt + 1);
				dp[u][mask] += dp[v][mask & (1 << color[v])];
			}
			dfs(v, 1 << color[v], 1);

			dp[u][mask] += dp[v][1 << color[v]];
		}
	}
	vis[u] = false;
}

int32_t main() {
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

	cin >> n >> m >> k;

	for (int u = 1; u <= n; ++u) {
		cin >> color[u];
		color[u]--;
	}
	
	for (int i = 0; i < m; ++i) {
		int u, v;
		cin >> u >> v;

		graph[u].push_back(v);
		graph[v].push_back(u);
	}

	dfs(1, (1 << color[1]), 1);

	cout << dp[1][(1 << color[1])] * 2 << "\n";
}

• Subtask 1: 0 / 23
• Subtask 2: 0 / 20
• Subtask 3: 0 / 27
• Subtask 4: 0 / 30