Cod sursa(job #1923420)

Utilizator PaulCbnCiobanu Paul PaulCbn Data 11 martie 2017 00:26:04
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.47 kb
#include <iostream>
#include <cstdio>
#include <vector>
#include <queue>

#define NMAX 50005
#define inf 0x3f3f3f3f

using namespace std;

int N,M;
vector<pair<int,int> > graf[NMAX];

void citire()
{
    scanf("%d%d",&N,&M);
    for(int i=1;i<=M;i++)
    {
        int x,y,c;
        scanf("%d%d%d",&x,&y,&c);
        graf[x].push_back(make_pair(y,c));
    }
}

int d[NMAX],viz[NMAX];
priority_queue<pair<int,int> > q;
void djikstra()
{
    for(int i=2;i<=N;i++)
        d[i]=inf;

    q.push(make_pair(0,1)); /// (-cost,nod)
    while(!q.empty())
    {
        int nod_curent = q.top().second;
        int cost_curent = -q.top().first;

        q.pop();

        if(viz[nod_curent])
            continue;
        viz[nod_curent]=1;

        for(vector<pair<int,int> >::iterator ii=graf[nod_curent].begin();ii!=graf[nod_curent].end();ii++)
        {
            int nod_nou = ii->first;
            int cost_nou = ii->second;

            if(cost_nou + d[nod_curent] < d[nod_nou])
            {
                d[nod_nou]= cost_nou + d[nod_curent];

                q.push(make_pair(-d[nod_nou],nod_nou));
            }
        }

    }
}

void afisare()
{
    for(int i=2;i<=N;i++)
        if(d[i]!=inf)
            printf("%d ",d[i]);
        else
            printf("0 ");
}

int main()
{
    freopen("dijkstra.in","r",stdin);
    freopen("dijkstra.out","w",stdout);
    citire();
    djikstra();
    afisare();
    return 0;
}