Longest_String_Chain

Author: Partho Biswas

README.md

@@ -791,7 +791,7 @@ BFS, DFS, Dijkstra, Floyd–Warshall, Bellman-Ford, Kruskal, Prim's, Minimum Spa
 
 ### 4. Dynamic Programming
 
-<details><summary>Problem sstatement from AlgoExpert.io with solutions and tutorials/videos</summary>
+<details><summary>Problem statement from AlgoExpert.io with solutions and tutorials/videos</summary>
 <p>
 
 | #  | Title | Solution | Tutorial | Level | Remarks |
@@ -810,14 +810,15 @@ BFS, DFS, Dijkstra, Floyd–Warshall, Bellman-Ford, Kruskal, Prim's, Minimum Spa
 |12| [Max_Profit_With_K_Transactions](algoexpert.io/questions/Max_Profit_With_K_Transactions.md) | [Python](algoexpert.io/python/Max_Profit_With_K_Transactions.py) |
 |13| [Palindrome_Partitioning_Min_Cuts](algoexpert.io/questions/Palindrome_Partitioning_Min_Cuts.md) | [Python](algoexpert.io/python/Palindrome_Partitioning_Min_Cuts.py) |
 |14| [Longest_Increasing_Subsequence](algoexpert.io/questions/Longest_Increasing_Subsequence.md) | [Python](algoexpert.io/python/Longest_Increasing_Subsequence.py) | [Video 1](https://www.youtube.com/watch?v=fV-TF4OvZpk), [Video 2](https://www.youtube.com/watch?v=CE2b_-XfVDk), , [Video 3](https://www.hackerrank.com/challenges/longest-increasing-subsequent/problem)|
+|15| [Longest_String_Chain](algoexpert.io/questions/Longest_String_Chain.md) | [Python](algoexpert.io/python/Longest_String_Chain.py) | --- |
 
 </p>
 </details>
 
 
 ### 5. Famous Algorithm
 
-<details><summary>Problem sstatement from AlgoExpert.io with solutions and tutorials/videos</summary>
+<details><summary>Problem statement from AlgoExpert.io with solutions and tutorials/videos</summary>
 <p>
 
 | #  | Title | Solution | Tutorial | Level | Remarks |

algoexpert.io/python/Longest_String_Chain.py

@@ -0,0 +1,43 @@
+def longestStringChain(strings):
+    stringChains = {}
+    for string in strings:
+        stringChains[string] = {"nextString": "", "maxChainLen": 1}
+
+    sortedString = sorted(strings, key=len)
+    for string in sortedString:
+        findLongestStringChain(string, stringChains)
+
+    return buildLongestStringChain(strings, stringChains)
+
+
+def findLongestStringChain(currentString, stringChains):
+    for i in range(len(currentString)):
+        smallerString = currentString[:i] + currentString[i + 1:]
+        if smallerString in stringChains:
+            smallerStringChainLen = stringChains[smallerString]["maxChainLen"]
+            currentStringChainLen = stringChains[currentString]["maxChainLen"]
+            if smallerStringChainLen + 1 > currentStringChainLen:
+                stringChains[currentString]["maxChainLen"] = smallerStringChainLen + 1
+                stringChains[currentString]["nextString"] = smallerString
+
+
+def buildLongestStringChain(strings, stringChains):
+    maxChainLen = 0
+    chainStartingString = ""
+    for string in strings:
+        if stringChains[string]["maxChainLen"] > maxChainLen:
+            maxChainLen = stringChains[string]["maxChainLen"]
+            chainStartingString = string
+
+    longestStringChain = []
+    currentString = chainStartingString
+    while currentString != "":
+        longestStringChain.append(currentString)
+        currentString = stringChains[currentString]["nextString"]
+    return [] if len(longestStringChain) == 1 else longestStringChain
+
+
+
+
+
+