Submission #566900

#	Time	Username	Problem	Language	Result	Execution time	Memory
566900		inluminas	Paths (BOI18_paths)	C++17	100 / 100	360 ms	58936 KiB

paths

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

#define ll long long
#define endl "\n"
#define fastio ios_base::sync_with_stdio(false)
#define inf LLONG_MAX
#define l first
#define r second

const int lmt=3e5+10;
vector<int>adj[lmt];

int main(){
	fastio;

	int n,m,k;
	cin>>n>>m>>k;
	ll dp[n+1][(1<<k)];
	int col[n+1];
	for(int i=1;i<=n;i++) cin>>col[i];

	vector<int>T[k+1];
	
	for(int i=0;i<(1<<k);i++){
		int cnt=__builtin_popcount(i);
		T[cnt].push_back(i);
	}

	for(int i=1;i<=m;i++){
		int u,v;
		cin>>u>>v;
		adj[u].push_back(v);
		adj[v].push_back(u);
	}

	for(int i=1;i<=n;i++){
		for(int j=0;j<(1<<k);j++) dp[i][j]=0;
	}

	for(int i=1;i<=n;i++){
		dp[i][(1<<(col[i]-1))]=1;
	}

	ll ans=0;

	for(int j=2;j<=k;j++){
		for(int i=1;i<=n;i++){
			for(int v:adj[i]){
				for(int val:T[j-1]){
					if(val&(1<<(col[i]-1))) continue;
					dp[i][val|(1<<(col[i]-1))]+=dp[v][val];
				}
			}
		}
	}

	for(int i=1;i<=n;i++){
		for(int j=2;j<=k;j++){
			for(int val:T[j]){
				ans+=dp[i][val];
			}
		}
	}

	cout<<ans<<endl;
	return 0;
}

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