Create longest-string-chain.py

Author: kamyu104

Python/longest-string-chain.py

@@ -0,0 +1,18 @@
+# Time:  O(n * l^2)
+# Space: O(n * l)
+
+import collections
+
+
+class Solution(object):
+    def longestStrChain(self, words):
+        """
+        :type words: List[str]
+        :rtype: int
+        """
+        words.sort(key=len)
+        dp = collections.defaultdict(int)
+        for w in words:
+            for i in xrange(len(w)):
+                dp[w] = max(dp[w], dp[w[:i]+w[i+1:]]+1)
+        return max(dp.itervalues())