Create 0383 Ransom Note.md

Author: jjjllxx

hashtable/0383 Ransom Note.md

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+# 383. Ransom Note
+https://leetcode-cn.com/problems/ransom-note/  
+Given two strings ransomNote and magazine, return true if ransomNote can be constructed from magazine and false otherwise.  
+Each letter in magazine can only be used once in ransomNote.  
+
+Example 1:  
+Input: ransomNote = "a", magazine = "b"  
+Output: false  
+
+Example 2:  
+Input: ransomNote = "aa", magazine = "ab"  
+Output: false  
+
+Example 3:   
+Input: ransomNote = "aa", magazine = "aab"  
+Output: true  
+
+Constraints:   
+1 <= ransomNote.length, magazine.length <= 10^5  
+ransomNote and magazine consist of lowercase English letters.  
+
+## hashtable
+``` python3
+class Solution:
+    def canConstruct(self, ransomNote: str, magazine: str) -> bool:
+        note_dict=Counter(ransomNote)
+        maga_dict=Counter(magazine)
+        for k,v in note_dict.items():
+            if k not in maga_dict.keys() or maga_dict[k]<v:
+                return False
+        return True
+```
+
+## bucket
+``` python3
+class Solution:
+    def canConstruct(self, ransomNote: str, magazine: str) -> bool:
+        note_dict=defaultdict(int)
+        for i in ransomNote:
+            note_dict[i]+=1
+        maga_dict=defaultdict(int)
+        for i in magazine:
+            maga_dict[i]+=1
+        for i in ransomNote:
+            if i not in maga_dict or note_dict[i]>maga_dict[i]:
+                return False
+        return True
+```
+