Given two strings X and Y, we need to convert string X into an anagram of string Y with minimum replacements. If we have multiple ways of achieving the target, we go for the lexicographically smaller string where length of each string
Input : X = "CDBABC" Y = "ADCABD" Output : Anagram : ADBADC Number of changes made : 2 Input : X = "PJPOJOVMAK" Y = "FVACRHLDAP" Output : Anagram : ACPDFHVLAR Number of changes made : 7
Approach used :
We have to convert string X into lexicographically smallest anagram of string Y doing minimum replacements in the original string X. We maintain two counter arrays which store the count/frequency of each character in the two strings. Let counters of the two strings be and . Now, anagrams by definition mean that the frequency of the characters in two anagrams is always equal. Thus, to convert string X into an anagram of string Y, the frequency of characters should be equal. Therefore, the total number of alteration we need to make in total to convert string X into an anagram of string Y is
, where we iterate for each character i.
Half job is done as we know how many replacements are to be done. We now need the lexicographically smaller string. Now, for a specific position, we look for all possible characters from ‘A’ to ‘Z’ and check for each character whether it could be fit in this position or now. For a better understanding, we iterate for each position in the string. Check if is there is a character which is there in string Y and not in string X (or the frequency of character is more in string Y and less in string X). Now, if there is one, we check that the character at current position in X, is it unnecessary? i.e. does it have more frequency in string X and less frequency in string Y. Now, if all the boxes are ticked, we further check the if we insert the character in this position, as we need to generate the lexicographically smaller string.If all the conditions are true, we replace the character in string X with the character in string Y. After all such replacements, we can print the altered string X as the output.
Anagram : ADBADC Number of changes made : 2
The overall time complexity is and as we ignore constants, the complexity is
- Minimum reduce operations to covert a given string into a palindrome
- Number of sub-strings which are anagram of any sub-string of another string
- Check if any anagram of a string is palindrome or not
- Find the character in first string that is present at minimum index in second string
- Minimum deletions from string to reduce it to string with at most 2 unique characters
- Minimum changes required to make first string substring of second string
- Minimum length of string having all permutation of given string.
- Minimize the number of replacements to get a string with same number of 'a', 'b' and 'c' in it
- Maximum and minimum sums from two numbers with digit replacements
- Minimum replacements to make elements of a ternary array same
- Remove minimum number of characters so that two strings become anagram
- Minimum rotations required to get the same string
- Minimum cost to construct a string
- Lexicographically minimum string rotation | Set 1
- Minimum Distance Between Words of a String
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