Submission #500279

#	Time	Username	Problem	Language	Result	Execution time	Memory
500279		couplefire	Robot (JOI21_ho_t4)	C++17	100 / 100	163 ms	20332 KiB

Main

#include <bits/stdc++.h>
#define fi first
#define se second
#define mp make_pair
using namespace std;

struct edge {
	int v,c,cost;
	edge(){}
	edge(int _v, int _c, int _cost) {
		v = _v;
		c = _c;
		cost = _cost;
	}
};
 
const int N = 1e5 + 5;
const int M = 2e5 + 5;
const long long oo = 1e18;
 
vector <edge> adj[N];
 
long long dis[2 * N];
long long sum[M];
long long best[M];
 
int n,m;
 
template <typename T> 
bool mini(T &a, T b) {
	if (a > b) {
		a = b;
		return true;
	}
	return false;
}
 
int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cin >> n >> m;
	for (int i = 1; i <= m; i++) {
		int u,v,c,w;
		cin >> u >> v >> c >> w;
		edge a = edge(v, c, w);
		edge b = edge(u, c, w);
		adj[u].push_back(a);
		adj[v].push_back(b);
	}
	for (int i = 1; i <= n; i++)
		dis[i] = oo;
	
	for (int i = 1; i <= m; i++)
		best[i] = oo;
 
	dis[1] = 0;
	priority_queue <pair <long long, int>> heap;
	heap.push(mp(0, 1));
	while (heap.size()) {
		int u = heap.top().se;
		long long cur = -heap.top().fi;
		heap.pop();
		if (cur != dis[u])
			continue;
 
		for (edge e : adj[u]) {
			sum[e.c] += e.cost;
			best[e.c] = min(best[e.c], dis[e.v]);
		}
 
		for (edge e : adj[u]) {
			int v = e.v;
			int c = e.c;
			int w = e.cost;
			long long tmp = min(0LL + w, sum[c] - w);
			if (mini(dis[v], cur + tmp)) 
				heap.push(mp(-dis[v], v));
 
			if (mini(dis[v], best[c] + sum[c] - w))
				heap.push(mp(-dis[v], v));
		}
 
		for (edge e : adj[u]) {
			sum[e.c] = 0;
			best[e.c] = oo;
		}
	}
	if (dis[n] == oo)
		dis[n] = -1;
	cout << dis[n];
}

• Subtask 1: 34 / 34
• Subtask 2: 24 / 24
• Subtask 3: 42 / 42