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Cod sursa(job #702909)
#include<cstdio>
#include<fstream>
using namespace std;
FILE *fin=fopen("dijkstra.in","r");
ofstream fout("dijkstra.out");
const int inf = 1 << 30;
const int lung = 50001;
struct nod{int val,cost;
nod *next;
};
int h[lung],d[lung],poz[lung],k,i,n,m,a,b,cost;
nod *q,*v[lung];
inline void upheap(int x)
{int tata;
while (x > 1)
{ tata = x >> 1;
if (d[h[tata]] > d[h[x]])
{ poz[h[tata]] = x;
poz[h[x]] = tata;
h[x] = h[x] + h[tata] - (h[tata] = h[x]);
x = tata;
}
else
x = 1;
}
}
inline int downheap(int x)
{int fiu;
while (x <= k)
{ fiu = x;
if ((x<<1) <= k)
{ fiu = x << 1;
if (fiu + 1 <= k)
if (d[h[fiu+1]] < d[h[fiu]])
++fiu;
}
else
return 0;
if (d[h[fiu]] < d[h[x]])
{ poz[h[fiu]] = x;
poz[h[x]] = fiu;
h[x] = h[x] + h[fiu] - (h[fiu] = h[x]);
x = fiu;
}
else
return 0;
}
return 0;
}
inline void dijkstra()
{int min;
for (i=2;i<=n;++i)
{ poz[i] = -1;
d[i] = inf;
}
h[1] = poz[1] = 1;
++k;
while (k)
{ min = h[1];
h[1] = h[1] + h[k] - (h[k] = h[1]);
poz[h[1]] = 1;
--k;
downheap(1);
q = v[min];
while (q)
{ if (d[q->val] > d[min] + q->cost)
{ d[q->val] = d[min] + q->cost;
if (poz[q->val] != -1)
upheap(poz[q->val]);
else
{ h[++k] = q -> val;
poz[h[k]] = k;
upheap(k);
}
}
q = q -> next;
}
}
}
int main()
{ fscanf(fin,"%d %d",&n,&m);
for (i=1;i<=m;++i)
{ fscanf(fin,"%d %d %d",&a,&b,&cost);
q = new nod;
q -> next = v[a];
q -> val = b;
q -> cost = cost;
v[a] = q;
}
dijkstra();
for (i=2;i<=n;++i)
if (d[i] == inf)
fout << "0 ";
else
fout << d[i] << " ";
return 0;
}