Cod sursa(job #2505658)

Utilizator Vladv01Vlad Vladut Vladv01 Data 7 decembrie 2019 10:10:39
Problema Algoritmul Bellman-Ford Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.08 kb
#include <iostream>
#include <queue>
#include <fstream>
#include <vector>

using namespace std;

ifstream f("bellmanford.in");
ofstream g("bellmanford.out");

struct node{

    int y,c;
};

vector <node> a[50005];
int d[50005],viz[50005];

int inf=0x3f3f3f3f;

queue<int > q;

int x,y,c,n,m;

void cit()
{
    f>>n>>m;
    for(int i=1;i<=n;i++)
    {
        f>>x>>y>>c;
        a[x].push_back({y,c});
    }
}

int rezolv()
{
    d[1]=0;
    q.push(1);
    viz[1]=1;
    while(!q.empty())
    {
        int nod=q.front();
        q.pop();
        for(auto &i: a[nod])
         if (d[i.y] > d[nod] + i.c) {
                ++viz[i.y];
                if (viz[i.y] == n)
                    return 0;
                d[i.y] = d[nod] + i.c;
                q.push(i.y);
            }

    }
    return 1;
}

void afis() {
    for (int i = 2; i <= n; ++i)
        g<<d[i]<<" ";
}

int main()
{
    cit();
    for(int i=2;i<=n;i++)
        d[i]=inf;
    if(rezolv()==1)
        afis();
    else
        g<<"Ciclu negativ!";

    return 0;
}