题解 | #最长回文子串#简单易懂。

import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.nextLine();
        int len=0;
        for (int i = 0; i < s.length(); i++) {
            for (int j = i+1; j <= s.length(); j++) {
                StringBuilder builder = new StringBuilder();
                String sub = s.substring(i, j);
                builder.append(sub);
                if (sub.equals(builder.reverse().toString())){
                    if (sub.length()>len){
                        len=sub.length();
                    }
                }
            }
        }
        System.out.println(len);
    }
}