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38 lines
1.1 KiB
Python
38 lines
1.1 KiB
Python
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import math
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class Graph:
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def __init__(self, N = 0): # a graph with Node 0,1,...,N-1
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self.N = N
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self.W = [[math.inf for j in range(0,N)] for i in range(0,N)] # adjacency matrix for weight
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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
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def addEdge(self, u, v, w):
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self.dp[u][v] = w;
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def floyd_warshall(self):
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for k in range(0,self.N):
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for i in range(0,self.N):
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for j in range(0,self.N):
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self.dp[i][j] = min(self.dp[i][j], self.dp[i][k] + self.dp[k][j])
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def showMin(self, u, v):
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return self.dp[u][v]
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if __name__ == '__main__':
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graph = Graph(5)
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graph.addEdge(0,2,9)
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graph.addEdge(0,4,10)
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graph.addEdge(1,3,5)
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graph.addEdge(2,3,7)
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graph.addEdge(3,0,10)
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graph.addEdge(3,1,2)
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graph.addEdge(3,2,1)
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graph.addEdge(3,4,6)
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graph.addEdge(4,1,3)
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graph.addEdge(4,2,4)
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graph.addEdge(4,3,9)
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graph.floyd_warshall()
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graph.showMin(1,4)
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graph.showMin(0,3)
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