Submission #376433

#	Time	Username	Problem	Language	Result	Execution time	Memory
376433		YJU	Paprike (COI18_paprike)	C++14	100 / 100	76 ms	21228 KiB

paprike

#include<bits/stdc++.h>
#pragma GCC optimize("unroll-loops,no-stack-protector,Ofast")
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<ll,ll> pll;
const ll MOD=1e9+7;
const ll MOD2=998244353;
const ll N=2e5+5;
const ld pi=acos(-1);
const ll INF=(1LL<<60);
#define SQ(i) ((i)*(i))
#define REP(i,n) for(ll i=0;i<n;i++)
#define REP1(i,n) for(ll i=1;i<=n;i++)
#define pb push_back
#define mp make_pair
#define X first
#define Y second
#define setp setprecision
#define lwb lower_bound
#define SZ(_a) (ll)_a.size()

ll n,k,sum[N],ans,x,y,w[N];
vector<ll> v[N];

void DFS(ll nd,ll pa){
	vector<ll> lis;
	for(ll i:v[nd]){
		if(i==pa)continue;
		DFS(i,nd);
		lis.pb(sum[i]);
	}
	sort(lis.begin(),lis.end());
	sum[nd]=w[nd];
	for(auto i:lis){
		if(sum[nd]+i>k)++ans;
		else sum[nd]+=i;
	}
}

int main(){
	ios_base::sync_with_stdio(0);cin.tie(0);
	cin>>n>>k;
	REP1(i,n)cin>>w[i];
	REP(i,n-1)cin>>x>>y,v[x].pb(y),v[y].pb(x);
	DFS(1,0);
	cout<<ans<<"\n";
	return 0;
}

• Subtask 1: 11 / 11
• Subtask 2: 13 / 13
• Subtask 3: 27 / 27
• Subtask 4: 49 / 49