Cod sursa(job #1091170)

Utilizator SebiSebiPirtoaca George Sebastian SebiSebi Data 24 ianuarie 2014 18:17:33
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.41 kb
#include<iostream>
#include<fstream>
#include<vector>
#include<queue>
using namespace std;

#define NMAX 50001
#define INF (1<<30)

struct Nod {
	int y,cost;
	Nod() {
		y=0;
		cost=0;
	}
	inline Nod(int _y, int _cost) {
		y=_y;
		cost=_cost;
	}
	inline bool operator < (const Nod &x) const {
		return cost>x.cost;
	}
};

priority_queue <Nod> c;
int viz[NMAX];

class Graph {
	
	vector <Nod> v[NMAX];
	int n;
	
public:
	
	Graph (int _n) {
		n=_n;
	}
	
	Graph () {
		n=0;
	}
	
	void addEdge(int x, int y, int cost = 0) {
		v[x].push_back(Nod(y,cost));
	}
	
	void setNodes(int _n) {
		n=_n;
	}
	
	void dijkstra(int nod, int d[]) {
		int i;
		for(i=1;i<=n;i++) {
			d[i]=INF;
			viz[i]=0;
		}
		d[nod]=0;
		c.push(Nod(nod,0));
		while(c.empty()==0) {
			nod=c.top().y;
			c.pop();
			if(viz[nod]==0) {
				viz[nod]=1;
				for(vector <Nod> :: iterator it=v[nod].begin();it!=v[nod].end();it++) 
					if(d[it->y]>d[nod]+it->cost) {
						d[it->y]=d[nod]+it->cost;
						c.push(Nod(it->y,d[it->y]));
					}
			}
		}
	}
};

Graph G;
int d[NMAX];

int main ()
{
	int n,m,i,x,y,cost;
	ifstream f("dijkstra.in");
	ofstream g("dijkstra.out");
	f>>n>>m;
	G.setNodes(n);
	for(i=1;i<=m;i++) {
		f>>x>>y>>cost;
		G.addEdge(x,y,cost);
	}
	f.close();
	G.dijkstra(1,d);
	for(i=2;i<=n;i++) {
		if(d[i]==INF)
			g<<"0";
		else g<<d[i];
		g<<" ";
	}
	g.close();
	return 0;
}