Submission #338410

#	Time	Username	Problem	Language	Result	Execution time	Memory
338410		amunduzbaev	Biochips (IZhO12_biochips)	C++14	0 / 100	7 ms	5996 KiB

biochips

/** made by amunduzbaev **/
#include <bits/stdc++.h>
using namespace std;
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define ub upper_bound
#define lb lower_bound
#define ll long long 
#define ld long double 
#define pii pair<int, int>
#define pll pair<ll, ll>
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(),x.rend()
#define fastios ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define vll vector<ll>
#define vii vector<int>
#define vpii vector<pii>
#define vpll vector<pll>
#define cnt(a)__builtin_popcount(a)
const int N = 2e5+5;
const int mod = 1e9+7;
const ll inf = 1e18;
const ld Pi = acos(-1);
int n, m, k, ans, pp[N], used[N], a[N];
vii edgess[N];

bool dfsp(int u){
	if(pp[u] == u) return 0;
	if(used[pp[u]])return 1;
	return dfsp(pp[u]); 
}

bool dfss(int u){
	bool ok = 0;
	for(auto x:edgess[u]){
		if(used[x]) return 1;
		ok |= dfss(x);
	}return ok;
}

void solve(){
	fastios 
	cin>>n>>m;
	for(int i=1;i<=n;i++){
		int x, mem;
		cin>>x>>mem;
		pp[i] = x;
		edgess[x].pb(i);
		a[i] = mem;
	}
	
	
	for(int i=0;i<(1<<n);i++){
		if(__builtin_popcount(i) != m) continue;
		memset(used, 0, sizeof used);
		bool ok = 1;
		
		for(int j=0;j<n;j++) if(i & (1<<j)) used[j+1] = 1;
		for(int j=0;j<n && ok;j++) if(used[j+1]) if(dfsp(j+1) || dfss(j+1)) ok = 0;
		
		if(ok){
			int tmpans = 0;
			for(int j=0;j<n;j++) if(used[j+1]) tmpans += a[j+1];
			ans = max(ans, tmpans);
		}
	}cout<<ans<<endl;
	return;
}
 
int main(){
	fastios
	int t = 1;
	if(t) solve();
	else {
		cin>>t;
		while (t--) solve();
	}
	return 0;
}

• Subtask 1: 0 / 100