Submission #731646

#	Time	Username	Problem	Language	Result	Execution time	Memory
731646		NintsiChkhaidze	Paths (BOI18_paths)	C++17	100 / 100	339 ms	56660 KiB

paths

#include <bits/stdc++.h>
#define ll long long
#define pb push_back
using namespace std;

const int N = 3e5 + 5;
ll dp[37][N];
int c[N];
vector <int> v[N];

signed main(){
	ios_base::sync_with_stdio(0),cin.tie(NULL),cout.tie(NULL);
	
	int n,m,k;
	cin>>n>>m>>k;
	
	for (int i = 1; i <= n; i++){
		cin>>c[i];
		--c[i];
		dp[(1<<c[i])][i] = 1;
	}
	for (int i = 1; i <= m; i++){
		int a,b;
		cin>>a>>b;
		v[a].pb(b);
		v[b].pb(a);
	}
	
	for (int mask = 0; mask < (1<<k); mask++){
		for (int i = 1; i <= n; i++){
			if (dp[mask][i] && (mask & (1<<c[i])) > 0) {
				for (int to: v[i]){
					if (!(mask & (1<<c[to]))){
						dp[mask ^ (1<<c[to])][to] += dp[mask][i];
					}
				}
			}
		}
	}
	
	ll ans=0;
	for (int i = 1; i <= n; i++){
		for (int mask = 0; mask < (1<<k); mask++){
			if ((mask & (1<<c[i])) > 0 && __builtin_popcount(mask) > 1)
				ans += dp[mask][i];
		}
	}
	cout<<ans;
}

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