mirror of
https://github.com/TheAlgorithms/Python.git
synced 2024-11-27 15:01:08 +00:00
43 lines
1.2 KiB
Python
43 lines
1.2 KiB
Python
import math
|
|
|
|
|
|
class Graph:
|
|
def __init__(self, N=0): # a graph with Node 0,1,...,N-1
|
|
self.N = N
|
|
self.W = [
|
|
[math.inf for j in range(0, N)] for i in range(0, N)
|
|
] # adjacency matrix for weight
|
|
self.dp = [
|
|
[math.inf for j in range(0, N)] for i in range(0, N)
|
|
] # dp[i][j] stores minimum distance from i to j
|
|
|
|
def addEdge(self, u, v, w):
|
|
self.dp[u][v] = w
|
|
|
|
def floyd_warshall(self):
|
|
for k in range(0, self.N):
|
|
for i in range(0, self.N):
|
|
for j in range(0, self.N):
|
|
self.dp[i][j] = min(self.dp[i][j], self.dp[i][k] + self.dp[k][j])
|
|
|
|
def showMin(self, u, v):
|
|
return self.dp[u][v]
|
|
|
|
|
|
if __name__ == "__main__":
|
|
graph = Graph(5)
|
|
graph.addEdge(0, 2, 9)
|
|
graph.addEdge(0, 4, 10)
|
|
graph.addEdge(1, 3, 5)
|
|
graph.addEdge(2, 3, 7)
|
|
graph.addEdge(3, 0, 10)
|
|
graph.addEdge(3, 1, 2)
|
|
graph.addEdge(3, 2, 1)
|
|
graph.addEdge(3, 4, 6)
|
|
graph.addEdge(4, 1, 3)
|
|
graph.addEdge(4, 2, 4)
|
|
graph.addEdge(4, 3, 9)
|
|
graph.floyd_warshall()
|
|
graph.showMin(1, 4)
|
|
graph.showMin(0, 3)
|