Cod sursa(job #1360735)

Utilizator ooptNemes Alin oopt Data 25 februarie 2015 17:33:03
Problema Algoritmul Bellman-Ford Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 1.19 kb
// dijkstra
#include <queue>
#include <iostream>
#include <fstream>
#include <vector>

#define NMax 50005
#define inf (1<<30)+100
#define pb push_back
#define mp make_pair

using namespace std;

ifstream f("dijkstra.in");
ofstream g("dijkstra.out");

struct cmp {
	bool operator()(const pair<int, int> &a, const pair<int, int> &b) {
		if (a.first < b.first)
			return false;
		if (a.first == b.first && a.second < b.second)
			return false;
		return true;
	}
};

int n,m;
vector<int> V[NMax];
vector<int> C[NMax];
priority_queue<pair<int, int>, vector< pair<int, int> >, cmp> q;
int dist[NMax];

void read() {
	f>>n>>m;
	for (int i=1;i<=m;i++) {
		int a,b,c;
		f>>a>>b>>c;
		V[a].pb(b);
		C[a].pb(c);
	}	
}

void solve() {
	for (int i=1;i<=n;i++)
		dist[i] = inf;
	dist[1] = 0;

	q.push(mp(0,1));

	while (!q.empty()) {
		int nod = q.top().second;
		int cost = q.top().first;
		q.pop();

		for (unsigned i=0;i<V[nod].size();i++) {
			int vecin = V[nod][i];
			if (dist[vecin] > cost + C[nod][i]) {
				dist[vecin] = cost + C[nod][i];
				q.push(mp(dist[vecin], vecin));
			}
		}
	}

	for (int i=2;i<=n;i++)
		g<<((dist[i]==inf)?0:dist[i])<<' ';
}

int main() {
	
	read();
	solve();

	f.close(); g.close();
	return 0;
}