Cod sursa(job #938415)

Utilizator tibi9876Marin Tiberiu tibi9876 Data 12 aprilie 2013 16:50:18
Problema Algoritmul lui Dijkstra Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.88 kb
#include<fstream>
#include<vector>
#include<queue>
using namespace std;

struct st
{
	int x,y;
	bool operator <(const st a)const 
	{
		return a.y<y;
	}
};

priority_queue <st> h;
vector <int> a[50001],cst[50001];
int c[50001],i,n,m,x,y,z;

st mk(int x,int y)
{
	st a;
	a.x=x;
	a.y=y;
	return a;
}

void solve()
{
	int i,x;
	while (!h.empty())
	{
		x=h.top().x;
		if (c[x]!=0)
		{
			h.pop();
			break;
		}
		c[x]=h.top().y;
		for (i=0;i<a[x].size();i++)
			if (c[a[x][i]]==0)
				h.push(mk(a[x][i],c[x]+cst[x][i]));
		h.pop();
	}
}				

int main()
{
	ifstream f("dijkstra.in");
	ofstream g("dijkstra.out");
	f >> n >> m;
	for (i=1;i<=m;i++)
	{
		f >> x >> y >> z;
		a[x].push_back(y);
		cst[x].push_back(z);
		a[y].push_back(x);
		cst[y].push_back(z);
	}
	h.push(mk(1,1));
	solve();
	for (i=2;i<=n;i++)
		g << c[i]-1 << ' ';
	return 0;
}