Longest path between any pair of vertices

def DFS(graph, src, prev_len,

max_len, visited):

visited[src] = 1

curr_len = 0

adjacent = None

for i in range(len(graph[src])):

adjacent = graph[src][i]

if (not visited[adjacent[0]]):

curr_len = prev_len + adjacent[1]

DFS(graph, adjacent[0], curr_len,

max_len, visited)

if (max_len[0] < curr_len):

max_len[0] = curr_len

curr_len = 0

def longestCable(graph, n):

max_len = [-999999999999]

for i in range(1, n + 1):

visited = [False] * (n + 1)

DFS(graph, i, 0, max_len, visited)

return max_len[0]

if __name__ == '__main__':

n = 6

graph = [[] for i in range(n + 1)]

graph[1].append([2, 3])

graph[2].append([1, 3])

graph[2].append([3, 4])

graph[3].append([2, 4])

graph[2].append([6, 2])

graph[6].append([2, 2])

graph[4].append([6, 6])

graph[6].append([4, 6])

graph[5].append([6, 5])

graph[6].append([5, 5])

print("Maximum length of cable =",

longestCable(graph, n))