Cod sursa(job #1736885)

Utilizator flaviu_2001Craciun Ioan-Flaviu flaviu_2001 Data 2 august 2016 20:42:06
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.34 kb
#include <fstream>
#include <vector>
#include <queue>
#define MAX 50005
#define INF 1<<30

using namespace std;

struct data{
    int edge, weight;
} nd;

vector<data> v[MAX];
queue<int> Queue;

int nodes, edges, distances[MAX];
int initial_point(1);

void scan();
void solve();
void write();

int main(){
    scan();
    solve();
    write();
    return 0;
}

void scan(){
    ifstream fin ("dijkstra.in");
    fin >> nodes >> edges;
    int x, y, z, m = edges;
    while(m--){
        fin >> x >> y >> z;
        nd.edge = y, nd.weight = z;
        v[x].push_back(nd);
    }
    for (int i = 1; i <= nodes; ++i)
        distances[i] = INF;
    fin.close();
}

void solve(){
    distances[initial_point] = 0;
    Queue.push(initial_point);

    while(!Queue.empty()){
        int k = Queue.front();
        for (unsigned int i = 0; i < v[k].size(); ++i)
            if (distances[v[k][i].edge] > distances[k] + v[k][i].weight)
                distances[v[k][i].edge] = distances[k] + v[k][i].weight,
                Queue.push(v[k][i].edge);
        Queue.pop();
    }
}

void write(){
    ofstream fout ("dijkstra.out");
    for (int i = 1; i <= nodes; ++i)
        if (i == initial_point)
            continue;
        else fout << (distances[i] == INF ? 0 : distances[i]) << " ";
    fout.close();
}