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Cod sursa(job #634846)
#include <stdio.h>
#include <vector>
#include <algorithm>
using namespace std;
#define maxn 50010
#define maxm 250010
#define inf 1000000000
#define pb push_back
#define mp make_pair
struct muchie
{
long x, y, c;
} M[maxm];
long n, m, i, j, k, left, right, cost[maxn], f[maxn];
vector <long> v[maxn];
vector <pair<long, long> > h;
void init()
{
long i;
cost[1]=0;
for(i=2; i<=n; i++)
cost[i]=inf;
h.pb(mp(0, 1));
make_heap(h.begin(), h.end());
}
void bellmanford()
{
pair<long, long> per;
long i, j, nod, poz;
long long pas=0;
while(h.size() && pas<=1LL*n*m)
{
pas++;
pop_heap(h.begin(), h.end());
per=h.back();
h.pop_back();
nod=per.second;
f[nod]=0;
for(j=0; j<v[nod].size(); j++)
{
poz=v[nod][j];
if(cost[M[poz].x]+M[poz].c<cost[M[poz].y])
{
cost[M[poz].y]=cost[M[poz].x]+M[poz].c;
if(!f[M[poz].y])
{
f[M[poz].y]=1;
h.pb(mp(-cost[M[poz].y], M[poz].y));
push_heap(h.begin(), h.end());
}
}
}
}
}
long verif_negativ()
{
long i;
for(i=1; i<=m; i++)
if(cost[M[i].x]+M[i].c<cost[M[i].y])
return 1;
return 0;
}
int main()
{
freopen("dijkstra.in", "r", stdin);
freopen("dijkstra.out", "w", stdout);
scanf("%d%d", &n, &m);
for(i=1; i<=m; i++)
{
scanf("%d%d%d", &M[i].x, &M[i].y, &M[i].c);
v[M[i].x].pb(i);
}
init();
bellmanford();
if(verif_negativ())
{
printf("Ciclu negativ!\n");
return 0;
}
for(i=2; i<=n; i++)
printf("%d ", cost[i]);
return 0;
}