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#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#define N 50001
#define M 250001
#define INF 1e9
typedef struct element element;
struct element
{
int vf, c, urm;
};
int lst[N], d[N], nrq[N], q[N], n, nr, st, dr;
element succesori[M];
bool inq[N];
int urmator(int p)
{
if (p == N - 1)
{
return 0;
}
return p + 1;
}
void adauga_q(int x)
{
dr = urmator(dr);
q[dr] = x;
inq[x] = true;
nrq[x]++;///la fiecare intrare in q, am gasit un drum mai lung optim
}
bool q_vida()
{
return (st == urmator(dr));
}
void sterge_q()
{
inq[q[st]] = false;
st = urmator(st);
}
bool bellman(int x0)
{
int i;
for (i = 1; i <= n; i++)
{
if (i == x0)
{
d[i] = 0;
adauga_q(i);
}
else
{
d[i] = INF;
}
}
while (!q_vida())
{
int x = q[st];
sterge_q();
int p = lst[x];
while (p != 0)
{
int y = succesori[p].vf;
int c = succesori[p].c;
if (d[x] + c < d[y])
{
d[y] = d[x] + c;
if (!inq[y])///daca y nu e deja in q
{
adauga_q(y);///il adaug
if (nrq[y] == n)///am gasit un drum optim de lungime n
{
return false;///deci am circuit negativ
}
}
}
p = succesori[p].urm;
}
}
return true;
}
void adauga(int x, int y, int c)
{
++nr;
succesori[nr].vf = y;
succesori[nr].c = c;
succesori[nr].urm = lst[x];
lst[x] = nr;
}
int main()
{
FILE *in, *out;
in = fopen("bellmanford.in", "r");
out = fopen("bellmanford.out", "w");
int m, i;
fscanf(in, "%d%d", &n, &m);
for (i = 0; i < m; i++)
{
int x, y, c;
fscanf(in, "%d%d%d", &x, &y, &c);
adauga(x, y, c);
}
fclose(in);
if (!bellman(1))
{
fprintf(out, "Ciclu negativ!");
}
else
{
for (i = 2; i <= n; i++)
{
fprintf(out, "%d ", d[i]);
}
}
fclose(out);
return 0;
}