so..i found this on wikipedia

but i dont really get what dist, previous, alt mean in here..

```
1 function Dijkstra(Graph, source):
2 for each vertex v in Graph: // Initializations
3 dist[v] := infinity ; // Unknown distance function from source to v
4 previous[v] := undefined ; // Previous node in optimal path from source
5 end for ;
6 dist[source] := 0 ; // Distance from source to source
7 Q := the set of all nodes in Graph ;
// All nodes in the graph are unoptimized - thus are in Q
8 while Q is not empty: // The main loop
9 u := vertex in Q with smallest dist[] ;
10 if dist[u] = infinity:
11 break ; // all remaining vertices are inaccessible from source
12 end if ;
13 remove u from Q ;
14 for each neighbor v of u: // where v has not yet been removed from Q.
15 alt := dist[u] + dist_between(u, v) ;
16 if alt < dist[v]: // Relax (u,v,a)
17 dist[v] := alt ;
18 previous[v] := u ;
19 end if ;
20 end for ;
21 end while ;
22 return dist[] ;
23 end Dijkstra.
```