prims algorithm.py

Author: dhyanbk

greedy_methods/prims algorithm.py

@@ -0,0 +1,24 @@
+def prims_algorithm(n, cost):
+    visited = [0] * (n + 1)  # Initialize visited array
+    visited[1] = 1  # Start from the first vertex
+    mincost = 0
+    ne = 1  # Number of edges in the spanning tree
+
+    print("The edges of the spanning tree are:")
+
+    while ne < n:
+        min_cost = float('inf')
+        a = b = -1  # Initialize edge endpoints
+
+        for i in range(1, n + 1):
+            if visited[i]:  # Check only visited vertices
+                for j in range(1, n + 1):
+                    if not visited[j] and cost[i][j] < min_cost:
+                        min_cost = cost[i][j]
+                        a, b = i, j
+
+        if a != -1 and b != -1:  # Ensure valid edge found
+            print(f"{ne}: edge({a}, {b}) = {min_cost}\t")
+            mincost += min_cost
+            visited[b] = 1
+            ne += 1