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Cod sursa(job #604492)
#include <iostream>
#include <vector>
#include <queue>
#define NMax 50005
#define Inf 2000000000
#define v first
#define c second
using namespace std;
vector < pair <int, int> > G[NMax];
int N, D[NMax], NQ[NMax];
queue <int> Q;
bool InQ[NMax], NC;
void Read ()
{
freopen ("bellmanford.in", "r", stdin);
int M;
scanf ("%d %d", &N, &M);
for (; M>0; --M)
{
int X, Y, Z;
scanf ("%d %d %d", &X, &Y, &Z);
G[X].push_back (make_pair (Y, Z));
}
}
void Print ()
{
freopen ("bellmanford.out", "w", stdout);
if (NC)
{
printf ("Ciclu negativ!\n");
}
else
{
for (int i=2; i<=N; ++i)
{
printf ("%d ", D[i]);
}
printf ("\n");
}
}
void Initialize (int Start)
{
for (int i=1; i<=N; ++i)
{
D[i]=Inf;
}
D[Start]=0;
InQ[Start]=true;
NQ[Start]=1;
Q.push (Start);
}
void BellmanFord (int Start)
{
Initialize (Start);
while (!Q.empty ())
{
int X=Q.front ();
Q.pop ();
InQ[X]=false;
for (unsigned i=0; i<G[X].size (); ++i)
{
int V=G[X][i].v;
int C=G[X][i].c;
if (D[X]+C<D[V])
{
D[V]=D[X]+C;
if (!InQ[V])
{
Q.push (V);
InQ[V]=true;
}
++NQ[V];
if (NQ[V]>=N)
{
NC=true;
return;
}
}
}
}
}
int main()
{
Read ();
BellmanFord (1);
Print ();
return 0;
}