Cod sursa(job #2350962)

Utilizator FunnyStockyMihnea Andreescu FunnyStocky Data 21 februarie 2019 20:40:30
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.1 kb
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

ifstream cin("bellmanford.in");
ofstream cout("bellmanford.out");

typedef long long ll;

const int N=50000+5;
const int M=250000+5;

struct edge
{
    int a,b,c;
};

int n,m;

int d[N];
edge e[M];
vector<int>v[N];
priority_queue<pair<int,int>>q;

int main()
{
    cin>>n>>m;
    for(int i=1;i<=m;i++)
    {
        cin>>e[i].a>>e[i].b>>e[i].c;
        v[e[i].a].push_back(i);
    }
    for(int i=2;i<=n;i++) d[i]=(1<<30);
    q.push({0,1});
    for(ll i=0;i<=n*(ll)m/2 && !q.empty();i++)
    {
        int nod=q.top().second;
        q.pop();
        for(auto it:v[nod])
        {
            if(d[nod]+e[it].c<d[e[it].b])
            {
                d[e[it].b]=d[nod]+e[it].c;
                q.push({-d[e[it].b],e[it].b});
            }
        }
    }
    for(int i=1;i<=m;i++)
    {
        if(d[e[i].a]+e[i].c<d[e[i].b])
        {
            cout<<"Ciclu negativ!\n";
            return 0;
        }
    }
    for(int i=2;i<=n;i++) cout<<d[i]<<" ";
    cout<<"\n";
    return 0;
}