Mai intai trebuie sa te autentifici.
Cod sursa(job #2422433)
Utilizator | Data | 18 mai 2019 18:43:17 | |
---|---|---|---|
Problema | Algoritmul lui Dijkstra | Scor | 50 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva educationala | Marime | 1.23 kb |
#include <iostream>
#include <fstream>
#include <vector>
using namespace std;
ifstream f ("dijkstra.in");
ofstream g ("dijkstra.out");
struct Edge
{
int cost,nod;
Edge(int cost1,int nod1);
};
Edge::Edge(int cost1,int nod1)
{
cost=cost1;
nod=nod1;
}
int main()
{
int n,m,i,j,c,a,b,vmin,ind,inf;
f>>n>>m;
inf=(n-1)*20000;
vector<vector<Edge>>G(n+1);
vector<int>d(n+1,inf);
vector<int>viz(n+1,0);
for(i=1; i<=m; i++)
{
f>>a>>b>>c;
G[a].push_back(Edge(c,b));
}
d[1]=0;
for(i=1; i<n; i++)
{
vmin=inf;
ind=-1;
for(j=1; j<=n; j++)
if(viz[j]==0 && d[j]<vmin)
{
vmin=d[j];
ind=j;
}
if(ind==-1) // nu toate nodurile sunt accesibile => la un moment dat nu mai gaseste noduri cu d[nod]<inf => ind=-1 =>incearca sa relaxeze -1 => crapa
break;
for(auto edge:G[ind])
if(d[edge.nod]>d[ind]+edge.cost)
d[edge.nod]=d[ind]+edge.cost;
viz[ind]=1;
}
for(i=2; i<=n; i++)
{
if(d[i]==inf)
d[i]=0;
g<<d[i]<<" ";
}
return 0;
}