Print anagrams together in Python using List and Dictionary

Given an array of words, print all anagrams together ?

Examples:

Input : arr = ['cat', 'dog', 'tac', 'god', 'act']
Output : 'cat tac act dog god'

Recommended: Please try your approach on {IDE} first, before moving on to the solution.

This problem has existing solution please refer Anagrams and Given a sequence of words, print all anagrams together links. We will solve this problem in python using List and Dictionary data structures. Approach is very simple :

Traverse list of strings.
Sort each string in ascending order and consider this sorted value as Key and original value as Value of corresponding key. Check if key is not present in dictionary that means it is occuring first time,
so map a empty list to Key and append value in it, if key is already present then simple append the value.
Now each key will contain list of strings which are anagram together.

# Function to return all anagrams together 
def allAnagram(input): 
      
    # empty dictionary which holds subsets  
    # of all anagrams together 
    dict = {} 
  
    # traverse list of strings 
    for strVal in input: 
          
        # sorted(iterable) method accepts any  
        # iterable and rerturns list of items 
        # in ascending order 
        key = ''.join(sorted(strVal)) 
          
        # now check if key exist in dictionary 
        # or not. If yes then simply append the   
        # strVal into the list of it's corresponding  
        # key. If not then map empty list onto 
        # key and then start appending values 
        if key in dict.keys(): 
            dict[key].append(strVal) 
        else: 
            dict[key] = [] 
            dict[key].append(strVal) 
  
     # traverse dictionary and concatenate values  
     # of keys together 
     output = "" 
     for key,value in dict.iteritems(): 
         output = output + ' '.join(value) + ' '
  
     return output 
  
# Driver function 
if __name__ == "__main__": 
    input=['cat', 'dog', 'tac', 'god', 'act'] 
    print allAnagram(input) 

Output:

'cat tac act dog god'

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