368. Largest Divisible Subset

Author: Partho Biswas

README.md

@@ -709,6 +709,7 @@ BFS, DFS, Dijkstra, Floyd–Warshall, Bellman-Ford, Kruskal, Prim's, Minimum Spa
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+|54| **[368. Largest Divisible Subset](https://tinyurl.com/ya8sv5jr)** | [Python](https://tinyurl.com/wu6rdaw/368_Largest_Divisible_Subset.py), [Swift](https://tinyurl.com/wuja3c4/368_Largest_Divisible_Subset.swift)| Official Solution | Medium | **Interesting problem.** |
 
 
 </p>

leetcode.com/python/368_Largest_Divisible_Subset.py

@@ -0,0 +1,71 @@
+# DP bottom-up tabulation
+class Solution(object):
+    def largestDivisibleSubset(self, nums):
+        """
+        :type nums: List[int]
+        :rtype: List[int]
+        """
+        # The container that holds all intermediate solutions.
+        # key: the largest element in a valid subset.
+        subsets = {-1: set()}
+
+        for num in sorted(nums):
+            currentSubSets = []
+            for key in subsets:
+                if num % key == 0:
+                    newSet = set(subsets[key])
+                    newSet.add(num)
+                    currentSubSets.append(newSet)
+            if currentSubSets is not None:
+                subsets[num] = max(currentSubSets, key=len)
+            else:
+                subsets[num] = {num}
+        return list(max(subsets.values(), key=len))
+
+
+# # DP top-down recursive - To Be Finished
+# class Solution(object):
+#     def largestDivisibleSubset(self, nums):
+#         """
+#         :type nums: List[int]
+#         :rtype: List[int]
+#         """
+#         # The container that holds all intermediate solutions.
+#         # key: the largest element in a valid subset.
+#         if not nums:
+#             return []
+#         nums.sort()
+#         memo = {}
+#         self.largestDivisibleSubsetHelper(nums, memo)
+#         return list(max(memo.values(), key=len))
+
+#     def largestDivisibleSubsetHelper(self, nums, memo):
+#         """
+#         :type nums: List[int]
+#         :rtype: List[int]
+#         """
+#         pass
+
+"""
+1,2,3
+  i
+    j
+
+1%2=0 or 2%1=0 > 1,2
+1%3=0 or 3%1=0 > 1,2
+
+
+1,2,4,8
+
+12 14 18 24 28 48 >>1248
+
+
+1248
+
+  1 2 4 8
+1 1  
+2   2 
+4     4 
+8       8
+
+"""