Submission #864401

#	Time	Username	Problem	Language	Result	Execution time	Memory
864401		iskhakkutbilim	Paths (BOI18_paths)	C++17	100 / 100	276 ms	95832 KiB

paths

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

#define int long long
#define ff first
#define ss second
#define all(a) a.begin(), a.end()
const int N = 3e5;
int n, m, col[N+1];
vector<int> g[N+1];
int ans;
int dp[N + 1][1<<5];


main(){
   ios::sync_with_stdio(0);
   cin.tie(0); cout.tie(0);
   int k;
	cin >> n >> m >> k;
	for(int i = 0;i < n; i++){
		cin >> col[i];
		col[i]--;
	}
	for(int i = 0;i < m; i++){
		int a, b; cin >> a >> b;
		a--, b--;
		g[a].push_back(b);
		g[b].push_back(a);
	}
	
	for(int i = 0;i < n; i++){
		dp[i][(1<<col[i])] = 1;
	}
	for(int mask = 0; mask < (1<<k); mask++){
		for(int v = 0; v < n; v++){
			if(!dp[v][mask]) continue;
			for(int to : g[v]){
				if(mask & (1<<col[to])) continue;
				dp[to][mask | (1<<col[to])]+= dp[v][mask];
			}
		}
	}
	for(int mask = 0; mask < (1<<k); mask++){
		if(__builtin_popcount(mask) < 2) continue;
		for(int i = 0;i < n; i++){
			ans+= dp[i][mask];
		}
	}
	cout << ans;
	return 0;
}

Compilation message (stderr)

paths.cpp:15:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   15 | main(){
      | ^~~~

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