Dijkstra’s algorithm in 3 minutes

today I'm going to teach you how to run Dijkstra's 
algorithm on a weighted directed graph Dijkstra's   algorithm tells you the shortest distance from one 
node to every other node in the graph this differs   from prims and kruskal's which result in minimum 
spanning trees let's use the following graph   for our example we'll keep a list of unvisited 
nodes at the bottom our first step is to pick   the starting node let's choose a we'll use the 
table on the right to keep track of distances   remember the distances we are measuring are from 
our starting node a we put 0 for a and infinity   for the others as we haven't visited them yet 
the next step is to examine the edges leaving   a we can reach B and C from a so let's update the 
chart with the corresponding costs next we look at   the chart and pick the smallest edge of which 
the vertex hasn't been chosen in this case C let's cross off see in the unvisited node list 
marking it as closed after choosing C we examine   the edges leaving seat and update the chart 
accordingly B is now reachable from a with the   cost of three by traveling through Z also D and 
E become reachable for the first time let's do   the same thing as before choosing the smallest 
path with a none closed node this time is B we   repeat the process examining the edges leaving 
B and updating the cost of getting to D and E now we choose D this time there are no updates 
to our table as there are no edges leaving D finally we choosey again there are no updates 
but this time because the edge leaving II does   not result in a shorter path all the edges in 
the graph have now been visited and are closed here is the shortest path 
from a to the other nodes the time complexity of Dyke shows is Big O of e 
+ V log B if a Fibonacci heap is used put simply   this is a result of creating the queue of distance 
values and looping through the edges of each node here is the pseudo code for Dijkstra's 
algorithm for more information please   visit the source shown below 
in the description and that's   it I hope this video gave you a good 
understanding of Dijkstra's algorithm