Submission #593661

#	Time	Username	Problem	Language	Result	Execution time	Memory
593661		8e7	Fireworks (APIO16_fireworks)	C++17	100 / 100	334 ms	80284 KiB

fireworks

//Challenge: Accepted
#include <bits/stdc++.h>
using namespace std;
#ifdef zisk
void debug(){cout << endl;}
template<class T,class ... U> void debug(T a, U ... b){cout << a << " ", debug(b...);}
template<class T> void pary(T l, T r) {
	while (l != r) cout << *l << " ", l++;
	cout << endl;
}
#else
#define debug(...) 0
#define pary(...) 0
#endif
#define ll long long
#define maxn 300005
#define pii pair<ll, ll>
#define ff first
#define ss second
#define io ios_base::sync_with_stdio(0);cin.tie(0);
#define se multiset<ll>

vector<pii> adj[maxn];

void merge(se &a, se &b) {
	if (b.size() > a.size()) swap(a, b);
	for (auto i:b) a.insert(i);
	b.clear();
}
ll vy[maxn]; //cost at 0
se dfs(int n) {
	se ret;	
	int chi = 0;
	for (auto [v, e]:adj[n]) {
		chi++;
		se tmp = dfs(v);
		ll pr = *prev(tmp.end());
		tmp.erase(prev(tmp.end()));
		ll pl = *prev(tmp.end());
		tmp.erase(prev(tmp.end()));
		tmp.insert(pl + e), tmp.insert(pr + e);
		vy[n] += vy[v] + e;
		merge(ret, tmp);
	}

	for (int i = 0;i < chi - 1;i++) {
		ret.erase(prev(ret.end()));	
	}
	if (chi == 0) {
		ret.insert(0);
		ret.insert(0);
	}
	return ret;	
}
int main() {
	io
	int n, m;
	cin >> n >> m;
	for (int i = 2;i <= n + m;i++) {
		int pi, ci;
		cin >> pi >> ci;
		adj[pi].push_back({i, ci});
	}
	se s = dfs(1);
	ll ans = vy[1], slope = -s.size() + 1, curx = 0;	
	for (auto i:s) {
		ans += slope * (i - curx);
		curx = i;
		slope++;
	}
	cout << ans << "\n";
}

• Subtask 1: 7 / 7
• Subtask 2: 19 / 19
• Subtask 3: 29 / 29
• Subtask 4: 45 / 45