Cod sursa(job #3324547)

Utilizator Laura721Laura Kudor Laura721 Data 22 noiembrie 2025 14:11:39
Problema Algoritmul lui Dijkstra Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.39 kb
#include <fstream>
#include <vector>
#include <queue>
using namespace std;
ifstream fin("dijkstra.in");
ofstream fout("dijkstra.out");
const int nmax=50000;
const int oo=1e9;
int d[nmax+5];
bool use[nmax+5];
struct Pair{
  int first,second;
};
vector <pair <int,int>> g[nmax+5];
priority_queue <pair<int,int>,vector <pair<int,int>>,greater <pair<int,int>>> q;
int n,m;
void read(){
    fin>>n>>m;
    for(int i=1;i<=m;++i){
        int x,y,c;
        fin>>x>>y>>c;
        //pair <int,int> p;
        //p=make_pair(y,c);
        //p.first=y; p.second=c;
        g[x].push_back(make_pair(y,c));
    }
}
int findmin(){
    while(use[q.top().second])
        q.pop();
    Min=q.top().second; q.pop();
    return Min;
}
void dijkstra(){
    for(int i=2;i<=n;i++)
        d[i]=oo;
    for(int i=1;i<=n;i++)
        q.push(make_pair(d[i],i));
    for(int i=1;i<=n;i++){
        int nod=findmin();
        use[nod]=true;
        for(auto i:g[nod]){
            int vecin=i.first,cost=i.second;
            if(d[nod+cost]<d[vecin]){
                d[vecin]=d[nod]+cost;
                q.push(make_pair(d[vecin],vecin);
            }
        }
    }
}
void print(){
    for(int i=2;i<=n;++i)
        if(d[i]==oo)
          d[i]=0;
    for(int i=2;i<=n;++i)
        fout<<d[i]<<" ";
    fout<<"\n";
}
int main()
{
    read();
    dijkstra();
    print();
    return 0;
}