Create floyd_warshall.py

floyd_warshall.py

@@ -0,0 +1,42 @@
+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)