Pagini recente » Cod sursa (job #649924) | Cod sursa (job #1450445) | Cod sursa (job #3003138) | Cod sursa (job #1742334) | Cod sursa (job #2158412)
#include <fstream>
#include <vector>
#include <set>
using namespace std;
ifstream fin("dijkstra.in");
ofstream fout("dijkstra.out");
const int INF = 99999999;
struct arc
{
int vf;
int cost;
friend bool operator < (const arc &src1, const arc &src2)
{
return src1.cost < src2.cost;
}
};
set<arc> heap;
arc minFromSet()
{
return *(heap.begin());
}
void insertArcInSet(int to, int cost)
{
arc a;
a.vf = to;
a.cost = cost;
heap.insert(a);
}
void eraseArcFromSet(int to, int cost)
{
arc a;
a.vf = to;
a.cost = cost;
heap.erase(a);
}
vector<arc> v[50010];
int d[50010], n, m;
int main()
{
fin >> n >> m;
for(int i = 1; i <= m; i++)
{
int x, y, c;
fin >> x >> y >> c;
arc aux;
aux.vf = y;
aux.cost = c;
v[x].push_back(aux);
}
int init = 1;
for(int i = 0 ; i <= n + 1; i++)
{
d[i] = INF;
}
int l = v[init].size();
d[init] = 0;
insertArcInSet(init, 0);
for(int i = 1; i <= n - 1; i++)
{
arc cmin = minFromSet();
int vf = cmin.vf;
heap.erase(cmin);
l = v[vf].size();
for(int j = 0; j < l; j++)
{
int vc = v[vf][j].vf;
int dist = v[vf][j].cost;
if(d[vf] + dist < d[vc])
{
if (d[vc] != INF)
{
eraseArcFromSet(vc, d[vc]);
}
d[vc] = d[vf] + dist;
insertArcInSet(vc, d[vc]);
}
}
}
for(int i = 2; i <= n; i++)
{
fout << ((d[i] == INF) ? 0 : d[i] ) << ' ';
}
return 0;
}