Cod sursa(job #401756)

Utilizator cezyGrigore Cezar cezy Data 23 februarie 2010 08:45:25
Problema Algoritmul lui Dijkstra Scor 90
Compilator cpp Status done
Runda Arhiva educationala Marime 1.04 kb
#include<fstream>
#include<vector>
#include<queue>
using namespace std;
#define nmax 50005
#define pb push_back
#define inf 1<<30
vector<int> g[nmax],c[nmax];
int viz[nmax],d[nmax];
int n,m,s=1;
void citire ()
{
	ifstream fin("dijkstra.in");
	int i,a,b,cost;
	fin>>n>>m;
	for(i=1;i<=m;i++)
	{
		fin>>a>>b>>cost;
		g[a].pb(b);
		c[a].pb(cost);
	}
	fin.close();
}
struct comp
{
	bool operator()(int i,int j)
	{
		return d[i]>d[j];
	}
};
priority_queue<int,vector<int>,comp> q;
void dijkstra(int nod)
{
	int i,k;
	for(i=1;i<=n;i++)
		d[i]=inf;
	q.push(nod);
	d[nod]=0;
	while(!q.empty())
	{
		k=q.top();
		viz[k]=0;
		q.pop();
		for(i=0;i<g[k].size();i++)
			if(d[g[k][i]]>d[k]+c[k][i])
			{
				d[g[k][i]]=d[k]+c[k][i];
				if(viz[g[k][i]]!=1)
					q.push(g[k][i]),viz[g[k][i]]=1;
			}
	}
}
void scrie()
{
	int i;
	ofstream fout("dijkstra.out");
	for(i=2;i<=n;i++)
		if(d[i]==inf) fout<<0<<' ';
		else fout<<d[i]<<' ';
	fout.close();
}
int main ()
{
	citire();
	dijkstra(s);
	scrie();
	return 0;
}