题解 | 最长回文子串

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        String str=in.nextLine();
        int left=0;
        int length=str.length();
        List<Integer> list=new ArrayList<>();
        int maxLength=0;
        for(int i=1;i<length-2;i++){
            int len1=expandAroundCenter(str,i,i);
            int len2=expandAroundCenter(str,i,i+1);
            maxLength=Math.max(maxLength,Math.max(len1,len2));
        }
        System.out.println(maxLength);
    }

    public static int expandAroundCenter(String s,int left,int right){
        while(left>=0&&right<s.length()&&s.charAt(left)==s.charAt(right)){
            left--;
            right++;
        }
        return right-left-1;
    }
}