Cod sursa(job #2476631)

Utilizator BogdanGhGhinea Bogdan BogdanGh Data 19 octombrie 2019 10:42:03
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.31 kb
#include <bits/stdc++.h>
#define inf 0x3f3f3f3f
using namespace std;
ifstream f("dijkstra.in");
ofstream g("dijkstra.out");
const int nmax=50005;
struct abc
{
    int nod,cost;
};
vector <abc>v[nmax];
priority_queue<pair<int, int>, vector<pair<int, int> >, greater<pair<int, int> > > heap;
int n,m,i,j,x,y,cost,a[nmax];
bool viz[nmax];
void solve()
{
    viz[1]=1;
    for(i=0; i<v[1].size(); i++)
    {
        heap.push({v[1][i].cost,v[1][i].nod});
        a[v[1][i].nod]=v[1][i].cost;
    }
    while(!heap.empty())
    {
        while(!heap.empty()&&viz[heap.top().second])
            heap.pop();

        if(heap.empty())break;

        cost=heap.top().first;
        x=heap.top().second;
        viz[x]=1;
        heap.pop();

        for(i=0; i<v[x].size(); i++)
        {
            int sum=v[x][i].cost+a[x];

            if(sum<a[v[x][i].nod])
            {
                a[v[x][i].nod]=sum;
                heap.push({sum,v[x][i].nod});
            }
        }
    }
}
int main()
{
    f>>n>>m;
    for(i=2; i<=n; i++)
        a[i]=inf;
    for(i=1; i<=m; i++)
    {
        f>>x>>y>>cost;
        v[x].push_back({y,cost});
    }
    solve();
    for(i=2; i<=n; i++)
        if(a[i]==inf)
            g<<"0 ";
        else
            g<<a[i]<<' ';
    return 0;
}