Cod sursa(job #3286306)

Utilizator staicumateiStaicu Matei Octavian staicumatei Data 13 martie 2025 23:11:34
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.44 kb
#include <bits/stdc++.h>

using namespace std;

ifstream fin("bellmanford.in");
ofstream fout("bellmanford.out");
const int nlim=250002;
const int oo=(1<<30);
int n;
int d[nlim];
int cnt[nlim];
bool viz[nlim];
vector <pair<int,int>> g[nlim];
struct compare{
    bool operator()(int x,int y)
    {
        return d[x]>d[y];
    }
};
priority_queue<int, vector<int>, compare>q;
void dijkstra(int nod)
{
    for(int i=1;i<=n;i++)
    {
        d[i]=oo;
    }
    cnt[nod]=1;
    d[nod]=0;
    q.push(nod);
    viz[nod]=true;
    while(!q.empty())
    {
        int nod=q.top();
        q.pop();
        viz[nod]=false;
        for(int i=0;i<g[nod].size();i++)
        {
            int v=g[nod][i].first;
            int c=g[nod][i].second;
            if(d[nod]+c<d[v])
            {
                d[v]=d[nod]+c;
                if(viz[v]==false)
                {
                    viz[v]=false;
                    q.push(v);
                    cnt[v]++;
                    if(cnt[v]>n)
                    {
                        fout<<"Ciclu negativ!";
                        exit(0);
                    }
                }
            }
        }
    }
}
int m,x,y,c;
int main()
{
    int k;
    fin>>n>>m;
    for(int i=1;i<=m;i++)
    {
        fin>>x>>y>>c;
        g[x].push_back(make_pair(y,c));
    }
    dijkstra(1);
    for(int i=2;i<=n;i++)
        fout<<d[i]<<" ";
    return 0;
}