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def dfs(i):
    status[i] = "visited" # mark the current node as visited
    for j in range(1,n+1): # iterate over all nodes
        if Graph[j][i] == 1: # if there is an edge from node j to node i
            if status[j] == "unvisited": # if node j has not been visited yet
                dfs(j) # recursively call the dfs function on node j
            elif status[j] == "visited": # if node j has already been visited
                print("cycle detected") # a cycle has been detected
                exit(0) # exit the program
    status[i] = "finished" # mark the current node as finished
    print(i) # print the current node

n = 5 # number of nodes in the graph
Graph = [[0 for j in range(n+1)] for i in range(n+1)] # create a n x n matrix to represent the graph
Graph[1][3] = 1
Graph[1][4] = 1
Graph[2][3] = 1
Graph[3][5] = 1
Graph[4][5] = 1

status = ["unvisited" for i in range(n+1)] # create a list to keep track of the status of each node (unvisited, visited, or finished)
adjacent = [0 for i in range(n+1)] # create a list to keep track of the number of adjacent nodes for each node

for i in range(1,n+1): # iterate over all nodes
    for j in range(1,n+1): # iterate over all nodes
        if Graph[i][j] == 1: # if there is an edge from node i to node j
            adjacent[i] += 1 # increment the number of adjacent nodes for node i

for i in range(1,n+1): # iterate over all nodes
    if adjacent[i] == 0: # if node i has no adjacent nodes
        dfs(i) # call the dfs function on node i


What I have tried:

so I have this assignment and my dr gave us the pseudo-code for it and told us to make it into an executable code.
I want the graph and output to be like this :
(1)->(3) /(1)->(4)/ (2)->(3)/ (3)->(5)/ (4)->(5)
1,2,3,4,5
and detect if there is a cycle I know that there is no cycle in this graph but if I wanted another graph I want to detect whether there is a cycle or not. I put a lot of comments to help you understand the code.
and thanks, guys.

here is the code that I wrote:
Posted
Comments
Graeme_Grant 26-May-23 17:41pm    
Ah, homework, always fun...

Progmatically walk the graph and output to screen or string.
Richard MacCutchan 27-May-23 4:21am    
Print out the node id and status each time in the loop.

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