中心扩散法 Java版本

import java.util.*;

public class Solution {
    public int getLongestPalindrome(String A, int n) {
        // write code here
        int length = A.length();
        int maxLen = 1;
        // 遍历C位
        for (int i = 0; i < length; i++) {
            int left = i - 1;
            int right = i + 1;
            int len = 1;
            // 判断左边是否与C位相同
            while (left >= 0 && A.charAt(left) == A.charAt(i)) {
                len++;
                left--;
            }
            // 判断右边是否与C位相同
            while (right < length && A.charAt(right) == A.charAt(i)) {
                len++;
                right++;
            }
            // 正常左右扩散
            while (left >= 0 && right < length && A.charAt(left) == A.charAt(right)) {
                len += 2;
                left--;
                right++;
            }
            maxLen = Math.max(maxLen, len);
        }
        return maxLen;
    }
}