Cod sursa(job #1121527)

Utilizator StickmanLazar Alexandru Stickman Data 25 februarie 2014 13:07:46
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.2 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

vector <long int> v[50001];
long int m,n,c,x,y,cost[50001],a,ok=1,ok2=1;
priority_queue < pair<int,int>, vector <pair<int,int> >, greater<pair<int,int> > > q;
bool visited[50001];

void dijkstra(int start)
{
    int i, k;
    visited[start]=0;
    while(!q.empty())
    {
        a=q.top().second;
        visited[a]=1;
        q.pop();
        for(k=0; k<v[a].size(); k+=2)
        {
            if(cost[a]+v[a][k+1]<cost[v[a][k]] && visited[v[a][k]]==0)
            {
                cost[v[a][k]]=cost[a]+v[a][k+1];
                q.push(make_pair(cost[v[a][k]],v[a][k]));
            }
        }
    }
}


int main()
{
    ifstream in("dijkstra.in");
    in>>n>>m;
    int i;
    for(i=0; i<m; i++)
    {
        in>>x>>y>>c;
        v[x].push_back(y);
        v[x].push_back(c);
    }
    for(i=2; i<=n; i++)
        cost[i]=99999991;
    q.push(make_pair(0,1));
    dijkstra(1);
    ofstream out("dijkstra.out");
    for(i=2; i<=n; i++)
        if(cost[i]==99999991)
            out<<0<<" ";
    else out<<cost[i]<<" ";
    in.close();
    out.close();
    return 0;
}