Cod sursa(job #2964981)

Utilizator LXGALXGA a LXGA Data 14 ianuarie 2023 11:08:25
Problema Algoritmul Bellman-Ford Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.27 kb
#include <fstream>
#include <algorithm>
#include <queue>
#include <vector>
using namespace std;
ifstream cin("bellmanford.in");
ofstream cout("bellmanford.out");
int n,m,d[50001],cnt[50001],a,b,c;
bool inq[500001];
vector<pair<int,int>> g[50001];
bool spfa(int nod)
{
    for(int i=1;i<=n;i++)
        d[i]=2e9;
    queue<int> q;
    q.push(nod);
    d[nod]=0;
    inq[nod]=1;
    while(!q.empty())
    {
        int a=q.front();
        q.pop();
        for(auto &i:g[a])
        {
            if(d[i.first]>d[a]+i.second)
            {
                d[i.first]=d[a]+i.second;
                if(!inq[i.first])
                {
                    inq[i.first]=1;
                    q.push(i.first);
                    cnt[i.first]++;
                    if(cnt[i.first]>=n)
                    {
                        cout<<"Ciclu negativ!";
                        return 0;
                    }
                }
            }
        }
    }
    return 1;
}
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cin>>n>>m;
    for(int i=1;i<=m;i++)
    {
        cin>>a>>b>>c;
        g[a].push_back({b,c});
    }
    if(!spfa(1))
        return 0;
    for(int i=2;i<=n;i++)
        cout<<d[i]<<' ';
    return 0;
}