Submission #990616

#	Time	Username	Problem	Language	Result	Execution time	Memory
990616		OAleksa	Cyberland (APIO23_cyberland)	C++17	49 / 100	3061 ms	51364 KiB

cyberland

#include "cyberland.h"
#include <bits/stdc++.h>
#define f first
#define s second
using namespace std;
//g++ cyberland.cpp cyberland.h stub.cpp
const int N = 1e5 + 69;
const long double inf = 1e18;
vector<pair<long long, long long>> g[N];
long double dis[N][33];
int vis[N], b[N];
void dfs(int v) {
	vis[v] = 1;
	for (auto u : g[v]) {
		if (vis[u.f])
			continue;
		if (b[u.f] == 0) {
			for (int j = 0;j <= 30;j++)
				dis[u.f][j] = 0;
		}
		else if (b[u.f] == 2) {
			for (int j = 0;j <= 30;j++) {
				dis[u.f][j] = min(dis[u.f][j], dis[v][j] + u.s);
				if (j < 30)
					dis[u.f][j + 1] = min(dis[u.f][j + 1], (dis[v][j] + u.s) / 2);
			}
		}
		else {
			for (int j = 0;j <= 30;j++) 
				dis[u.f][j] = min(dis[u.f][j], dis[v][j] + u.s);
		}
		dfs(u.f);
	}
}
double solve(int n, int m, int k, int s, vector<int> x, vector<int> y, vector<int> c, vector<int> a) {
	//reset
	for (int i = 0;i < n;i++) {
		g[i].clear();
		b[i] = a[i];
		vis[i] = 0;
	}
	int ok = 1;
	for (int i = 0;i < m;i++) {
		g[x[i]].push_back({y[i], c[i]});
		g[y[i]].push_back({x[i], c[i]});
		ok &= (x[i] + 1 == y[i]);
	}
	for (int i = 0;i < n;i++) {
		for (int j = 0;j <= k;j++)
			dis[i][j] = inf;
	}
	dis[0][0] = 0;
	if (ok && m == n - 1) {
		long double ans = inf;
		dfs(0);
		for (int i = 0;i <= k;i++)
			ans = min(ans, dis[s][i]);
		if (ans >= inf)
			ans = -1;
		assert(ans != -1);
		return ans;
	}
	priority_queue<tuple<double, int, int>> pq;
	pq.push({0, 0, 0});
	while (!pq.empty()) {
		auto x = pq.top();
		pq.pop();
		int v, j;
		double d;
		tie(d, v, j) = x;
		d = abs(d);
		if (a[v] == 0) {
			for (int j = 0;j <= k;j++)
				dis[v][j] = 0;
			d = 0;
		}
		for (auto u : g[v]) {
			if (dis[u.f][j] > d + u.s) {
				dis[u.f][j] = d + u.s;
				if (u.f != s)
					pq.push({-dis[u.f][j], u.f, j});
			}
			if (a[u.f] == 2) {
				if (j < k && dis[u.f][j + 1] > (d + u.s) / 2) {
					dis[u.f][j + 1] = (d + u.s) / 2;
					if (u.f != s)
						pq.push({-dis[u.f][j + 1], u.f, j + 1});
				}
			}
		}
	}
	long double ans = inf;
	for (int i = 0;i <= k;i++)
		ans = min(ans, dis[s][i]);
	if (ans == inf)
		ans = -1;
	return ans;
}

• Subtask 1: 5 / 5
• Subtask 2: 8 / 8
• Subtask 3: 13 / 13
• Subtask 4: 0 / 19
• Subtask 5: 7 / 7
• Subtask 6: 16 / 16
• Subtask 7: 0 / 29
• Subtask 8: 0 / 3