2019-09-03

Author: JiayangWu

0276.栅栏涂色/0276-栅栏涂色.py

@@ -0,0 +1,12 @@
+class Solution(object):
+    def numWays(self, n, k):
+        """
+        :type n: int
+        :type k: int
+        :rtype: int
+        """
+        dp = [0] * (n + 3)
+        dp[0], dp[1], dp[2] = 0, k, k * k
+        for i in range(3, n + 1):
+            dp[i] = dp[i - 1] * (k - 1) + dp[i - 2] * (k - 1)
+        return dp[n]

5176.猜字谜/5176-猜字谜.py

@@ -8,17 +8,17 @@ def findNumOfValidWords(self, words, puzzles):
         from collections import Counter
         for i in range(len(words)):
             words[i] = "".join(sorted(set(words[i])))
-        record = Counter(words) #统计每种单词出现的频率
+        record = Counter(words) #统计每种pattern出现的频率
 
         res = []
         for p in puzzles:
-            bfs = [p[0]]
+            bfs = [p[0]] #固定首字母
             for char in p[1:]:
-                bfs += [s + char for s in bfs]
+                bfs += [s + char for s in bfs] #生成64种可能
             cnt = 0
             for combination in bfs:
                 tmp = "".join(sorted(combination))
-                if tmp in record:
+                if tmp in record: #看看当前pattern在words里有没有出现过
                     cnt += record[tmp]
             res.append(cnt)
         return res