Cod sursa(job #3286742)

Utilizator filiptudose2007Tudose Filip filiptudose2007 Data 14 martie 2025 16:41:24
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.52 kb
#include <bits/stdc++.h>
using namespace std;
int n,m;
bool sel[50005];
int d[50005],nr[50005];
vector <pair<int,int>> G[50005];
bool bellmanford(int nod)
{
    for(int i=1; i<=n; ++i)
    {
        if(i==nod)
            continue;
        d[i]=INT_MAX;
    }
    sel[nod]=true;
    queue <int> q;
    bool done=true;
    q.push(nod);
    while(!q.empty() && done)
    {
        int k=q.front();
        q.pop();
        sel[k]=false;
        for(auto it: G[k])
        {
            if(nr[it.second]>n)
                done=false;
            else if(d[it.second]>d[k]+it.first)
            {
                d[it.second]=d[k]+it.first;
                if(!sel[it.second])
                {
                    q.push(it.second);
                    sel[it.second]=true;
                }
                nr[it.second]=nr[k]+1;
                if(nr[it.second]>n)
                    done=false;
            }



        }
    }
    return done;
}
int main()
{
    freopen("bellmanford.in","r",stdin);
    freopen("bellmanford.out","w",stdout);
    cin.sync_with_stdio(false);
    cin.tie(0);
    cin>>n>>m;
    for(int i=1; i<=m; ++i)
    {
        int x,y,z;
        cin>>x>>y>>z;
        G[x].push_back({z,y});
    }
    bool ok=bellmanford(1);
    if(!ok)
    {
        cout<<"Ciclu negativ!\n";
        return 0;
    }
    for(int i=2; i<=n; ++i)
    {
        if(d[i]!=INT_MAX)
            cout<<d[i];
        else
            cout<<0;
        cout<<' ';
    }
    return 0;
}