Submission #934708

#	Time	Username	Problem	Language	Result	Execution time	Memory
934708		MinaRagy06	Road Closures (APIO21_roads)	C++17	53 / 100	2040 ms	40136 KiB

roads

#include <bits/stdc++.h>
#ifdef MINA
#include "grader.cpp"
#endif
#include "roads.h"
using namespace std;
#define ll long long
 
const int N = 100'005;
int t[N], curt, dep[N], par[N], DEG[N], deg[N];
vector<array<int, 2>> adj[N], newadj[N];
vector<int> rem[N];
void build(int i, int p, int d = 0) {
	t[i] = curt++;
	for (auto &[nxt, w] : adj[i]) {
		if (nxt == p) continue;
		build(nxt, i, d + 1);
		newadj[t[i]].push_back({t[nxt], w});
	}
	par[t[i]] = t[p];
	dep[t[i]] = d;
}
ll dp[N][2], s[N], m;
vector<ll> vals[N];
vector<ll> minimum_closure_costs(int n, vector<int> u, vector<int> v, vector<int> W) {
	bool st1 = 1, st5 = 1;
	for (int i = 0; i < n - 1; i++) {
		adj[u[i]].push_back({v[i], W[i]});
		adj[v[i]].push_back({u[i], W[i]});
		st1 &= u[i] == 0;
		st5 &= W[i] == 1;
	}
	build(0, -1);
	for (int i = 0; i < n; i++) {
		adj[i] = newadj[i];
	}
	int mx = 0;
	for (int i = 0; i < n; i++) {
		DEG[i] = adj[i].size() + (i != 0);
		rem[DEG[i]].push_back(i);
		mx = max(mx, DEG[i]);
	}
	if (st1) {
		sort(adj[0].begin(), adj[0].end(), [&] (array<int, 2> x, array<int, 2> y) {return x[1] < y[1];});
		vector<ll> ret(n);
		ll s = 0;
		for (int i = n - 1; i >= 0; i--) {
			ret[i] = s;
			if (i > 0) s += adj[0][n - 1 - i][1];
		}
		return ret;
	} else if (st5) {
		set<int> cur;
		for (int i = 0; i < n; i++) cur.insert(i);
		vector<ll> ret(n, 0);
		for (m = 0; m < n; m++) {
			for (auto j : rem[m]) cur.erase(j);
			vector<int> v;
			for (auto i : cur) v.push_back(i), deg[i] = DEG[i];
			sort(v.begin(), v.end(), [&](int x, int y) {return dep[x] > dep[y];});
			for (auto j : v) {
				if (deg[j] > m) {
					ret[m] += deg[j] - m;
					deg[par[j]]--;
				}
			}
		}
		return ret;
	}
	vector<ll> ret(n);
	for (m = 0; m < n; m++) {
		if (m > mx) {
			ret[m] = ret[m - 1];
			continue;
		}
		for (int i = n - 1; i >= 0; i--) {
			s[i] = 0;
			vals[i].clear();
			dp[i][0] = dp[i][1] = 0;
			for (auto [nxt, w] : adj[i]) {
				dp[i][0] += dp[nxt][1];
				dp[i][1] += dp[nxt][1];
				vals[i].push_back(- dp[nxt][1] + dp[nxt][0] + w);
			}
			sort(vals[i].begin(), vals[i].end());
			int rem = adj[i].size() - m;
			int lst = 0;
			for (auto j : vals[i]) {
				if (j >= 0) break;
				lst++;
			}
			for (int j = 0; j < max(lst, rem); j++) {
				dp[i][0] += vals[i][j];
			}
			if (m == 0) {
				dp[i][1] = 1e18;
			} else {
				for (int j = 0; j < max(lst, rem + 1); j++) {
					dp[i][1] += vals[i][j];
				}
			}
		}
		ret[m] = dp[0][0];
	}
	return ret;
}

• Subtask 1: 5 / 5
• Subtask 2: 7 / 7
• Subtask 3: 14 / 14
• Subtask 4: 10 / 10
• Subtask 5: 17 / 17
• Subtask 6: 0 / 25
• Subtask 7: 0 / 22