Submission #895636

#	Time	Username	Problem	Language	Result	Execution time	Memory
895636		pcc	Paths (BOI18_paths)	C++14	100 / 100	323 ms	84820 KiB

paths

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

#define ll long long
#define pll pair<ll,ll>
#define pii pair<int,int>
#define fs first
#define sc second
#define tlll tuple<ll,ll,ll>


const int mxn = 3e5+10;
ll dp[33][mxn];
ll N,M,K;
int col[mxn];
vector<int> paths[mxn];

inline ll calc(int mask){
	ll re = 0;
	for(int i = 1;i<=N;i++){
		re += dp[mask][i];
		for(auto &nxt:paths[i]){
			if(mask&(1<<col[nxt]))continue;
			dp[mask^(1<<col[nxt])][nxt] += dp[mask][i];
		}
	}
	return re;
}

int main(){
	ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	cin>>N>>M>>K;
	for(int i = 1;i<=N;i++){
		cin>>col[i];
		col[i]--;
		dp[1<<col[i]][i] = 1;
	}
	for(int i = 0;i<M;i++){
		int a,b;
		cin>>a>>b;
		paths[a].push_back(b);
		paths[b].push_back(a);
	}
	ll ans = 0;
	for(int i = 1;i<(1<<K);i++){
		ll re = calc(i);
		if(__builtin_popcount(i)>1)ans += re;
	}
	cout<<ans;
}

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