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//Bellman-Ford, graf orientat
#include <iostream>
#include <fstream>
#define INF 9999
using namespace std;
ifstream in("bellmanford.in");
ofstream out("bellmanford.out");
int n,m;
struct muchie{
int x,y,cost;
}v[250005]; //vector muchii
int d[50005]; //vector distante minime st->i
int c[2500005]; //coada noduri vizitate
bool viz[250005]; //vector noduri vizitate (care se afla in coada)
void citire()
{
in>>n>>m;
for(int i=1;i<=m;++i)
in>>v[i].x>>v[i].y>>v[i].cost;
}
void bellmanFord(int st)
//drum distanta minima (fara coada)
{
//initilizeaza vectorul distante cu +INF
for(int i=1;i<=n;++i)
d[i]=+INF;
d[st]=0; //distanta st->st = 0
for(int k=1;k<=n-1;++k) //n-1 iteratii
{
for(int i=1;i<=n;++i) //ia muchiile exterioare ale fiecarui nod
{
for(int j=1;j<=m;++j) //parcurge vectorul de muchii
{
if(v[j].x==i) //daca gasesti o muchie exterioara SI obtii un drum st->fin(al) mai mic trecand prin int(ermediar)
if(d[v[j].y] > d[i] + v[j].cost) //daca( st->fin > st->int + int->fin )
d[v[j].y] = d[i] + v[j].cost;
}
}
}
for(int i=2;i<=n;++i)
out<<d[i]<<" ";
out<<"\n";
}
void bellmanFord1(int st)
//drum distanta minima (cu coada)
{
//initializez vectorul distante cu +INF
for(int i=1;i<=n;++i)
d[i]=+INF;
d[st]=0; //distanta st->st = 0
//declarari
int x,inc,sf;
int cnt=1;
inc=sf=1;
c[inc]=st;
viz[st]=1;
while(inc<=sf) //cat timp coada nu e vida ?SI nu am facut inca n-1 iteratii
{
x=c[inc++]; //ia urmatorul nod din coada (ca nod intermediar)
viz[x] = 0; //SI marcheaza nodul x ca nevizitat
for(int i=1;i<=m;++i) //parcurge vectorul de muchii
{
if(v[i].x==x) //daca gasesti o muchie exterioara x->nod
if(d[v[i].y] > d[x] + v[i].cost) //daca obtii un drum optim (st->fin > st->int + int->fin)
{
//actualizezi
d[v[i].y] = d[x] + v[i].cost;
//daca nodul final e nevizitat (nu se afla in coada)
if(viz[v[i].y] == 0)
{
c[++sf] = v[i].y; //adaugi nodul final in coada
viz[v[i].y] = 1; //SI marcheaza nodul ca vizitat
}
}
}
++cnt;
}
//afiseaza vectorul distante
for(int i=2;i<=n;++i)
out<<d[i]<<" ";
out<<"\n";
}
int main()
{
citire();
//bellmanFord(1);
bellmanFord1(1);
return 0;
}