Add prayatna solution

Lecture-06-DFS/prayatna.py

@@ -0,0 +1,41 @@
+
+MAX = 100005
+graph = [[] for _ in range(MAX)]
+visited = [False] * MAX
+
+# Adjacency List
+def read_graph(m):
+  for _ in range(m):
+    node_x, node_y = map(int, input().split())
+    graph[node_x].append(node_y)
+    graph[node_y].append(node_x)
+
+def dfs(root):
+  stack = []
+
+  visited[root] = True
+  stack.append(root)
+
+  while len(stack) > 0:
+    node = stack.pop()
+    for node_realated in graph[node]:
+      if not visited[node_realated]:
+        visited[node_realated] = True
+        stack.append(node_realated)
+
+t = int(input())
+for _ in range(t):
+  n = int(input())
+  # Reset
+  graph = [[] for _ in range(MAX)]
+  visited = [False] * MAX
+
+  e = int(input())
+  read_graph(e)
+
+  count = 0
+  for i in range(n):
+    if visited[i] == False:
+      dfs(i)
+      count += 1
+  print(count)

README.md

@@ -12,3 +12,4 @@ Solution for Big-O Blue course
 ## Lecture 6: DFS
 
 - Bishu and his Girlfriend (from: [Hackerrank](https://assessment.hackerearth.com/challenges/college/nits-local-10/algorithm/84888e824aa04fc793c3beefca02b5a7/))
+- Prayatna (from: [Spoj](https://vn.spoj.com/problems/CAM5/))