Cod sursa(job #2236051)

Utilizator DandeacDan Deac Dandeac Data 27 august 2018 23:16:57
Problema Algoritmul Bellman-Ford Scor 10
Compilator cpp Status done
Runda Arhiva educationala Marime 1.39 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <cstring>
#include <queue>
#include <algorithm>
using namespace std;

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

#define INF 0x3f3f3f3f
#define Gmax 50010


int dist[Gmax];
int N,M;

struct Graf
{
    int from;
    int to;
    int cost;
}G[Gmax];
int main()
{
    f>>N>>M;
    for(int i=1; i<=M; i++)
    {
        int x,y,c;
        f>>x>>y>>c;
        G[i].from = x;
        G[i].to = y;
        G[i].cost = c;

    }

    memset(dist, 0x3f, sizeof(dist));

    dist[1] = 0;
    for(int i=0; i<M-1;i++)
    {
        for(int j=1;j<=N;j++)
        {
            if(dist[G[j].from] + G[j].cost < dist[G[j].to])
                dist[G[j].to] = dist[G[j].from] + G[j].cost;
        }
    }

    for(int i=0; i<M-1;i++)
    {
        for(int j=1;j<=N;j++)
        {
            if(dist[G[j].from] + G[j].cost < dist[G[j].to])
                dist[G[j].to] = -INF;
        }
    }
    bool negative = false;
    for(int i=2; i<=N; i++)
    {
         if(dist[i]==-INF)
         {  g<<"Ciclu negativ!";
         negative = true;
            break;
         }

    }
    if(!negative)
   {
        for(int i=2; i<=N; i++)
        {
             if(dist[i]==INF) g<<0<<' ';
            else
                g<<dist[i] <<' ';
        }
    }


    return 0;
}