Added common-characters

Author: avidLearnerInProgress

common_characters.py

@@ -0,0 +1,31 @@
+class Solution:
+    def commonChars(self, A: List[str]) -> List[str]:
+        
+        ''' wrong approach --
+        res, hash_ = [], dict()
+        clist = [c for ele in A for c in ele]
+        for ch in clist:
+            hash_[ch] = hash_.get(ch, 0) + 1
+        for ele, c in hash_.items():
+            if c%len(A) == 0:
+                res.append(ele)
+        return res
+        '''
+        
+        #Naive non-pythonic code
+        '''
+        fin_res = []
+        check = set(A[0])
+        for l in check:
+            res = min([a.count(l) for a in A])
+            print(res)
+            fin_res.append([l] * res)
+        fi = [i for x in fin_res for i in x]
+        return sorted(fi)
+        '''
+        #power of list comprehensions
+        check = set(A[0])
+        result = [[l] * min([a.count(l) for a in A]) for l in check]
+        return sorted([i for e in result for i in e])
+        
+