Find and print the uncommon characters of the two given strings in sorted order. Here uncommon character means that either the character is present in one string or it is present in other string but not in both. The strings contain only lowercase characters and can contain duplicates.
Examples:
Input: str1 = “characters”, str2 = “alphabets”
Output: b c l p r
Input: str1 = “geeksforgeeks”, str2 = “geeksquiz”
Output: f i o q r u z
Naive Approach: Using two loops, for each character of 1st string check whether it is present in the 2nd string or not. Likewise, for each character of 2nd string check whether it is present in the 1st string or not.
Time Complexity: O(n^2) and extra would be required to handle duplicates.
Efficient Approach: An efficient approach is to use hashing.
Below is the implementation of the above approach:
# Python 3 implementation to find the # uncommon characters of the two strings # size of the hash table MAX_CHAR = 26 # function to find the uncommon characters # of the two strings def findAndPrintUncommonChars(str1, str2): # mark presence of each character as 0 # in the hash table 'present[]' present = [0] * MAX_CHAR for i in range(0, MAX_CHAR): present[i] = 0 l1 = len(str1) l2 = len(str2) # for each character of str1, mark its # presence as 1 in 'present[]' for i in range(0, l1): present[ord(str1[i]) - ord('a')] = 1 # for each character of str2 for i in range(0, l2): # if a character of str2 is also present # in str1, then mark its presence as -1 if(present[ord(str2[i]) - ord('a')] == 1 or present[ord(str2[i]) - ord('a')] == -1): present[ord(str2[i]) - ord('a')] = -1 # else mark its presence as 2 else: present[ord(str2[i]) - ord('a')] = 2 # print all the uncommon characters for i in range(0, MAX_CHAR): if(present[i] == 1 or present[i] == 2): print(chr(i + ord('a')), end = " ") # Driver Code if __name__ == "__main__": str1 = "characters" str2 = "alphabets" findAndPrintUncommonChars(str1, str2) # This code is contributed # by Sairahul099
Output:
b c l p r
Time Complexity: O(m + n), where m and n are the sizes of the two strings respectively.