131. Palindrome Partitioning

最新推荐文章于 2025-05-25 20:32:48 发布

原创最新推荐文章于 2025-05-25 20:32:48 发布 · 110 阅读

0 ·

CC 4.0 BY-SA版权

Leet Code 专栏收录该内容

143 篇文章

订阅专栏

本文深入探讨了一种用于回文字符串划分的算法，通过递归和动态规划的方法，找出所有可能的回文子串组合。文章详细解释了算法的工作原理，并提供了完整的代码实现。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

131. Palindrome Partitioning

Medium

Given a string s, partition s such that every substring of the partition is a palindrome.

Return all possible palindrome partitioning of s.

Example:

Input: "aab"
Output:
[
  ["aa","b"],
  ["a","a","b"]
]

class Solution {
    public List<List<String>> partition(String s) {
        if (null == s || s.length() < 1) {
            return new ArrayList();
        }
        int n = s.length();
        if (1 == s.length()) {
            return Arrays.asList(Arrays.asList(s));
        }
        
        char[] sc = s.toCharArray();
        boolean[][] bc = new boolean[n][n];
        for (int i = 0; i < n - 1; i++) {
            bc[i][i] = true;
            if (sc[i] == sc[i + 1]) {
                bc[i][i + 1] = true;
            }
        }
        bc[n - 1][n - 1] = true;
        
        // i indicates string length
        for (int i = 3; i <= n; i++) {
            // j indicates string index
            for (int j = 0; j <= n - i; j++) {
                boolean b = (sc[j] == sc[j + i - 1]);
                bc[j][j + i - 1] = b && bc[j + 1][j + i - 1 - 1];
            }
        }
        List<List<String>> result = new ArrayList<>();
        buildPalindrome(bc, result, new Stack<>(), s, 0, n);
        
        return result;
    }
    
    private void buildPalindrome(boolean[][] bc,
        List<List<String>> result, Stack<String> stack, 
        String s, int depth, int n) {
        if (n == depth) {
            result.add(new ArrayList(stack));
            return;
        }

        for (int i = depth; i < n; i++) {
            if (bc[depth][i]) {
                stack.push(s.substring(depth, i + 1));
                buildPalindrome(bc, result, stack, s, i + 1, n);
                stack.pop();
            }
        }
    }
}