Cod sursa(job #2799282)

Utilizator DMR6476Erdic Dragos DMR6476 Data 12 noiembrie 2021 19:31:55
Problema Algoritmul Bellman-Ford Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.57 kb
#include <iostream>
#include<bits/stdc++.h>
using namespace std;
ifstream fin("bellmanford.in");
ofstream fout("bellmanford.out");
const int INF=0x3f3f3f3f;
struct vertice
{
    int firstNode;
    int secondNode;
    int cost;
};
int distancesFromNodes[50005];
vector<vertice> neighbours;
int main()
{
    //
    int n,m;
    fin>>n>>m;
    for(int i=0; i<m; i++)
    {
        int x,y,cost;
        fin>>x>>y>>cost;
        neighbours.push_back({x,y,cost});
    }
    fin.close();
    for(int i=0; i<50005; i++)
        distancesFromNodes[i]=INF;
    distancesFromNodes[1]=0;

    for(int i=0; i<n-1; i++)
    {
        for(int j=0; j<m; j++)
        {
            vertice currentOne=neighbours[i];
            if(distancesFromNodes[currentOne.firstNode]+currentOne.cost<distancesFromNodes[currentOne.secondNode])
                distancesFromNodes[currentOne.secondNode]=distancesFromNodes[currentOne.firstNode]+currentOne.cost;
        }
    }
    for(int i=0; i<n-1; i++)
    {
        for(int j=0; j<m; j++)
        {
            vertice currentOne=neighbours[i];
            if(distancesFromNodes[currentOne.firstNode]+currentOne.cost<distancesFromNodes[currentOne.secondNode])
                distancesFromNodes[currentOne.secondNode]=-INF;
        }
    }
    bool isCycle=false;
    for(int i=1;i<=n;i++)
        if(distancesFromNodes[i]==-INF)
            isCycle=true;
    if(isCycle==false)
    for(int i=2;i<=n;i++)
        fout<<distancesFromNodes[i]<<" ";
    else
        fout<<"Ciclu negativ!";
    fout.close();
    return 0;
}