Optimal Partition of String

Given a string s, partition the string into one or more substrings such that the characters in each substring are unique. That is, no letter appears in a single substring more than once.

Return the minimum number of substrings in such a partition.

Note that each character should belong to exactly one substring in a partition.

LeetCode Problem - 2405

class Solution {
    public int partitionString(String s) {
        Set<Character> seenChars = new HashSet<>(); // Set to track characters seen in the current substring
        int numOfSubstrings = 1; // Initialize the count of substrings to 1

        // Iterate through each character in the string
        for (char c : s.toCharArray()) {
            // If the character has already been seen in the current substring
            if (seenChars.contains(c)) {
                // Increment the count of substrings
                numOfSubstrings++;
                // Clear the set to start tracking characters for the new substring
                seenChars.clear();
            }
            // Add the current character to the set
            seenChars.add(c);
        }

        // Return the total number of substrings
        return numOfSubstrings;
    }
}