Add medium problems

Author: das-jishu

Medium/degrees-of-separation.py

@@ -0,0 +1,50 @@
+
+# DEGREES OF SEPARATION
+
+# O(V + E) time, O(V) space
+def degreesOfSeparation(friendsLists, personOne, personTwo):
+    # Write your code here.
+    degrees, visited = {}, {}
+	findDegrees(friendsLists, personOne, degrees, visited, 0)
+	getUnconnectedPeople(friendsLists, degrees)
+	countOne = 0
+	for person in degrees:
+		if degrees[person] > 6:
+			countOne += 1
+	
+	print(degrees)
+	degrees, visited = {}, {}
+	findDegrees(friendsLists, personTwo, degrees, visited, 0)
+	getUnconnectedPeople(friendsLists, degrees)
+	countTwo = 0
+	for person in degrees:
+		if degrees[person] > 6:
+			countTwo += 1
+	print(degrees)		
+	if countOne < countTwo:
+		return personOne
+	elif countTwo < countOne:
+		return personTwo
+	else:
+		return ""
+
+def findDegrees(friendsLists, person, degrees, visited, level):
+	degrees[person] = 0
+	queue = [(person, 0)]
+	#visited = {person: True}
+	while queue:
+		current = queue.pop(0)
+		#visited[current[0]] = True
+		level = current[1]
+		for friend in friendsLists[current[0]]:
+			if friend in visited:
+				continue
+			visited[friend] = True
+			degrees[friend] = level + 1
+			queue.append((friend, level + 1))
+
+
+def getUnconnectedPeople(friendsLists, degrees):
+	for friend in friendsLists:
+		if friend not in degrees:
+			degrees[friend] = float("inf")