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// Java Stream solution for the palindrome partitioning problem
// This solution uses Java Streams for a more functional approach
// We use the same logic as the previous solution but with Streams

import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.IntStream;

public class PalindromePartitioningStream {
    public List<List<String>> partition(String s) {
        return partition(s, 0);
    }

    private List<List<String>> partition(String s, int start) {
        if (start == s.length()) {
            List<List<String>> result = new ArrayList<>();
            result.add(new ArrayList<>());
            return result;
        }

        return IntStream.range(start, s.length())
            .filter(i -> isPalindrome(s, start, i))
            .mapToObj(i -> partition(s, i + 1).stream()
                .peek(list -> list.add(0, s.substring(start, i + 1)))
                .collect(Collectors.toList()))
            .flatMap(List::stream)
            .collect(Collectors.toList());
    }

    private boolean isPalindrome(String s, int low, int high) {
        while (low < high) {
            if (s.charAt(low++) != s.charAt(high--)) return false;
        }
        return true;
    }

    public static void main(String[] args) {
        PalindromePartitioningStream solution = new PalindromePartitioningStream();
        System.out.println(solution.partition("google"));
        System.out.println(solution.partition("aab"));
        System.out.println(solution.partition("a"));
    }
}