Submission #259361

#	Time	Username	Problem	Language	Result	Execution time	Memory
259361		DrumpfTheGodEmperor	Fireworks (APIO16_fireworks)	C++14	0 / 100	13 ms	19072 KiB

fireworks

#include <bits/stdc++.h>
#define bp __builtin_popcountll
#define pb push_back
#define in(s) freopen(s, "r", stdin);
#define out(s) freopen(s, "w", stdout);
#define inout(s, end1, end2) freopen((string(s) + "." + end1).c_str(), "r", stdin),\
		freopen((string(s) + "." + end2).c_str(), "w", stdout);
#define fi first
#define se second
#define bw(i, r, l) for (int i = r - 1; i >= l; i--)
#define fw(i, l, r) for (int i = l; i < r; i++)
#define fa(i, x) for (auto i: x)
using namespace std;
const int mod = 1e9 + 7, inf = 1061109567;
const long long infll = 4557430888798830399;
const int N = 3e5 + 5;
int n, m, c[N], ptr[N];
vector<int> g[N];
struct slope {
	int a, b;
	priority_queue<int> pq;
	void move(int c) {
		//After pq.top() is slope 1.
		int curTop = pq.top();
		pq.pop();
		int nxtTop = -1;
		if (pq.size()) {
			nxtTop = pq.top();
			pq.pop();
		}
		pq.push(curTop + c);
		if (nxtTop != -1) pq.push(nxtTop + c);
		
		b -= c;
	}
	int pqSize() {
		return pq.size();
	}
	int getTop() {
		if (pq.empty()) return -1;
		int ans = pq.top();
		pq.pop();
		return ans;
	}
	void pushIn(int val) {
		pq.push(val);
	}
} dp[N];
void merge(slope &s1, slope &s2) {
	s1.a += s2.a;
	s1.b += s2.b;
	while (1) {
		int val = s2.getTop();
		if (val == -1) break;
		s1.pushIn(val);
	}
	//Pop off the top while the slope is still > 1
	while (s1.a > 1) {
		int x = s1.pq.top(); s1.pq.pop();
		s1.a--;
		s1.b += x;
	}
}
void dfs(int u) {
	if (g[u].size() == 0) {
//		cout << "uhh u = " << u + 1 << "\n";
		dp[u].pq.push(0);
		dp[u].pq.push(0);
		dp[u].a = 1, dp[u].b = 0;
		ptr[u] = u;
		return;
	}
	fa (v, g[u]) dfs(v);
//	cout << "U = " << u + 1 << "\n";
	fa (v, g[u]) dp[ptr[v]].move(c[v]);
//	cout << "all moves performed\n";
	int bigChild = -1;
	fa (v, g[u]) {
		if (bigChild == -1 || dp[ptr[v]].pqSize() > dp[ptr[bigChild]].pqSize()) bigChild = v;
	}
//	cout << "bigChild found = " << bigChild << "\n";
	ptr[u] = ptr[bigChild];
	fa (v, g[u]) if (v != bigChild) {
		merge(dp[ptr[u]], dp[ptr[v]]);
	}
}
signed main() {
	#ifdef BLU
	in("blu.inp");
	#endif
	ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
//	so uhh get dp(v) and move it to the right by C(v) units, merge it with |C(v) - X|
	cin >> n >> m;
	fw (i, 1, n + m) {
		int p;
		cin >> p >> c[i];
		p--;
		g[p].pb(i);
	}
//	a function actually only needs slope -1 -> 0 and 0 -> 1 moved when moving to the right
//	merging functions are just unioning their pqs and summing up a and b.
	dfs(0);
	slope s = dp[ptr[0]];
	int x = s.pq.top(), a = s.a, b = s.b;
	cout << x * a + b;
	return 0;
}

• Subtask 1: 0 / 7
• Subtask 2: 0 / 19
• Subtask 3: 0 / 29
• Subtask 4: 0 / 45