Submission #928272

#	Time	Username	Problem	Language	Result	Execution time	Memory
928272		vjudge1	Magic Tree (CEOI19_magictree)	C++17	3 / 100	74 ms	11308 KiB

magictree

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define ent "\n"

const int maxn = 1e5 + 100;
const ll INF = (ll)1e18 + 100;
const int MOD = 998244353;

int n, m, k;
vector<int> g[maxn];
vector<pii> q[maxn];
int f[maxn];
ll d[maxn * 4];

void upd(int i, ll x, int v = 1, int tl = 0, int tr = k){
	if(tl == tr) d[v] = x;
	else{
		int mid = (tl + tr) >> 1;
		if(i <= mid) upd(i, x, v<<1, tl, mid);
		else upd(i, x, v<<1|1, mid+1, tr);
		d[v] = max(d[v<<1], d[v<<1|1]);
	}
}

ll get(int l, int r, int v = 1, int tl = 0, int tr = k){
	if(tr < l || tl > r) return -INF;
	if(l <= tl && tr <= r) return d[v];
	int mid = (tl + tr) >> 1;
	return max(get(l, r, v<<1, tl, mid)
	, get(l, r, v<<1|1, mid+1, tr));
}

void calc(int v, int i){
	if(f[v]) return;
	f[v] = i;
	for(int to: g[v]){
		calc(to, i);
	}
}

void test(){
	cin >> n >> m >> k;
	for(int i = 2; i <= n; i++){
		int p; cin >> p;
		g[p].push_back(i);
	}
	for(int i = 1; i <= m; i++){
		int v, d, w;
		cin >> v >> d >> w;
		q[d].push_back({v, w});
	}
	for(int i = 1; i <= k; i++){
		vector<pii> s = {{0, 0}};
		for(auto [v, d]: q[i]){
			calc(v, i);
			s.push_back({f[v], d});
		}
		ll mx = 0, sum = 0;
		s.push_back({i, 0});
		sort(s.begin(), s.end());
		for(int i = s.size() - 1; i > 0; i--){
			sum += s[i].second;
			if(s[i-1].first < s[i].first){
				mx = max(mx, get(s[i-1].first, s[i].first - 1) + sum);
			}
		}
		upd(i, mx);
	}
	cout << get(k, k);
}

int main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);
    // #ifndef ONLINE_JUDGE
    //     freopen("input.txt", "r", stdin);
    //     freopen("output.txt", "w", stdout);
    // #endif
	int t; t = 1;
	while(t--) test();
}

• Subtask 1: 0 / 6
• Subtask 2: 3 / 3
• Subtask 3: 0 / 11
• Subtask 4: 0 / 12
• Subtask 5: 0 / 16
• Subtask 6: 0 / 13
• Subtask 7: 0 / 22
• Subtask 8: 0 / 17