From edaa2c15889b250c777f583fda5725cf073b18f2 Mon Sep 17 00:00:00 2001
From: Sarot Busala <sabuza97@gmail.com>
Date: Fri, 20 Oct 2017 16:26:07 +0700
Subject: [PATCH] Floyd Warshall Algorithm

upload simple Floyd-Warshall Algorithm (No path stored)
---
 dynamic_programming/FloydWarshall.py | 37 ++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)
 create mode 100644 dynamic_programming/FloydWarshall.py

diff --git a/dynamic_programming/FloydWarshall.py b/dynamic_programming/FloydWarshall.py
new file mode 100644
index 000000000..bf7714124
--- /dev/null
+++ b/dynamic_programming/FloydWarshall.py
@@ -0,0 +1,37 @@
+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)