1319: Number of Operations to Make Network Connected

Author: sumanth-botlagunta

python/no_of_operations_to_make_network_connected.py

@@ -0,0 +1,35 @@
+# https://leetcode.com/problems/number-of-operations-to-make-network-connected/description/
+# T: O(M) where M is the number of connections
+# S: O(N) where N is the number of nodes
+
+class Solution:
+    def makeConnected(self, n, connections) -> int:
+        if len(connections) < n-1:
+            return -1
+        if n == 1:
+            return 0
+        graph = {}
+        for a, b in connections:
+            if a in graph:
+                graph[a].append(b)
+            else:
+                graph[a] = [b]
+
+            if b in graph:
+                graph[b].append(a)
+            else:
+                graph[b] = [a]
+
+        visited = [0] * n
+
+        def dfs(node):
+            if visited[node]:
+                return 0
+            visited[node] = 1
+            if node in graph:
+                for num in graph[node]:
+                    dfs(num)
+            return 1
+            
+
+        return sum(dfs(node) for node in range(n)) - 1