Submission #814287

#	Time	Username	Problem	Language	Result	Execution time	Memory
814287		MohamedAhmed04	Robot (JOI21_ho_t4)	C++14	0 / 100	125 ms	16036 KiB

Main

#include <bits/stdc++.h>

using namespace std ;

const long long inf = 1e18 ;
const int MAX = 1e5 + 10 ;

int arr[MAX] ;
int n , m ;

vector< vector< array<int , 3> > >adj(MAX) ;

long long dist[MAX] ;

void dijkstra(int src)
{
	for(int i = 1 ; i <= n ; ++i)
		dist[i] = inf ;
	priority_queue< pair<long long , int> , vector< pair<long long , int> > , greater< pair<long long , int> > >q ;
	dist[src] = 0 ;
	q.push({0 , src}) ;
	while(!q.empty())
	{
		pair<long long , int>p = q.top() ;
		q.pop() ;
		int node = p.second ;
		long long cost = p.first ;
		if(dist[node] < cost)
			continue ;
		sort(adj[node].begin() , adj[node].end()) ;
		int sz = adj[node].size() ;
		for(int i = 0 ; i < sz ; ++i)
		{
			int child2 = adj[node][i][1] ;
			long long cost2 = cost + adj[node][i][2] ;
			if(cost2 < dist[child2])
			{
				dist[child2] = cost2 ;
				q.push({cost2 , child2}) ;
			}
			int cnt = 0 , idx = -1 ;
			if(i-1 >= 0 && adj[node][i][0] == adj[node][i-1][0])
				cnt++ , idx = i-1 ;
			if(i+1 < sz && adj[node][i][0] == adj[node][i+1][0])
				cnt++ , idx = i+1 ;
			if(i+2 < sz && adj[node][i][0] == adj[node][i+2][0])
				cnt++ , idx = i+2 ;
			cost2 = cost ;
			if(cost2 < dist[child2] && (cnt == 0 || (cnt == 1 && dist[adj[node][idx][1]] + adj[node][idx][2] == dist[node])))
			{
				dist[child2] = cost2 ;
				q.push({cost2 , child2}) ;
			}
		}
	}
}

int main()
{
	ios_base::sync_with_stdio(0) ;
	cin.tie(0) ;
	cin>>n>>m ;
	for(int i = 0 ; i < m ; ++i)
	{
		int x , y , c , w ;
		cin>>x>>y>>c>>w ;
		adj[x].push_back({c , y , w}) ;
		adj[y].push_back({c , x , w}) ;
	}
	dijkstra(1) ;
	if(dist[n] == inf)
		dist[n] = -1 ;
	return cout<<dist[n]<<"\n" , 0 ;
}		

• Subtask 1: 0 / 34
• Subtask 2: 0 / 24
• Subtask 3: 0 / 42