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c_cpp
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#include<iostream>
using namespace std;
#define MAX 9999

typedef struct edge
{
  int s;
  int d;
  int w;
}edge;

void bellman(int nv,edge e[],int sv,int ne)
{
  int u,v,weight,i,j=0;
  int dis[MAX];
  int parent[MAX]; // to keep each nodes parent

  //assigning infinity to the weights
  for(i=0;i<nv;i++)
  {
    dis[i]=MAX;
  }

  // distance of source vertex is o
  dis[sv]=0;
  parent[sv] = NULL; // source nodes parent is null

  //relaxing the edges v-1 time
  for(i=0;i<nv-1;i++)
  {
    for(j=0;j<ne;j++)
    {
      u=e[j].s;
      v=e[j].d;
      weight=e[j].w;


      if(dis[u]+weight < dis[v] && dis[u]!=MAX)
      {
        dis[v]=dis[u]+weight;
        parent[v] = u;
      }
    }

  }

  //negative cycle check
  for(j=0;j<ne;j++)
  {
    u=e[j].s;
    v=e[j].d;
    weight=e[j].w;

    if(dis[u]+weight < dis[v])
    {
      cout<<"\nThere is no shortest path.\n";
      return;
    }
  }

  cout<<"\nVertex"<<"  Shortest Cost From Source"<<"  Path";
  for(i=0;i<nv;i++)
  {
    cout<<"\n"<<i<<"\t"<<dis[i]<<"\t"<<"\t"<<"\t"<<"\t";
    
    //path
    int x = i;
    while(1){
      cout<<x<<"<-";
      x = parent[x];
      if(x == NULL) break;
    }
  }

}


int main()
{
  int nv,ne,sv;
  edge e[MAX];

  cout<<"Enter the number of vertex: ";
  cin>>nv;

  printf("Enter the source vertex of the graph: ");
  cin>>sv;

  cout<<"\nEnter no. of edges: ";
  cin>>ne;
  for(int i=0;i<ne;i++)
  {
    cout<<"\nFor "<<i+1<<"th Edge =>\n";
    cout<<"Enter Source, Destination & Edge Weight :";
    cin>>e[i].s>>e[i].d>>e[i].w;
  }
  bellman(nv,e,sv,ne);
  return 0;
}