Given a string containing lowercase English alphabets. The task is to find the minimum number of characters needed to be removed so that the remaining string contains at most 2 unique characters.
Note: The final string can have duplicate characters. The task is only to reduce the string with minimum deletions such that there can be a maximum of 2 unique characters in the resultant string.
Input: S = “geeksforgeeks”
After removing 7 characters the final string will be “geegee”
Input: S = “helloworld”
Approach: First count the occurrences of each character within the given string then just select two characters with maximum occurrence i.e. the two most frequently occurring characters in the string. And the result will be:
String length – (Occurrence of 1st most frequent character + Occurrence of 2nd most frequent character)
Below is the implementation of the above approach:
Time Complexity: O(N), where N is the length of the given String.
- Minimum number of deletions to make a string palindrome | Set 2
- Minimum number of deletions to make a string palindrome
- Reduce the string by removing K consecutive identical characters
- Determine if a string has all Unique Characters
- String with maximum number of unique characters
- Minimize number of unique characters in string
- Find the longest substring with k unique characters in a given string
- Python program to check if a string contains all unique characters
- Minimum reduce operations to covert a given string into a palindrome
- Minimum sum of squares of character counts in a given string after removing k characters
- Minimum characters to be added at front to make string palindrome
- Minimum number of characters to be removed to make a binary string alternate
- Minimal moves to form a string by adding characters or appending string itself
- Lexicographically smallest string formed by appending a character from the first K characters of a given string
- Create a new string by alternately combining the characters of two halves of the string in reverse
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