题解 | 最长回文子串

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);
        char[] originalChar = in.nextLine().toCharArray();
        int num = 0;
        int max = 0;
        for (int i = 0; i < originalChar.length; i++) {
            for (int j = originalChar.length - 1; j >= i; j--) {
                if (originalChar[i] == originalChar[j]) {
                    int left = i;
                    int right = j;
                    if (left == right) {
                        num = 1;
                    } else {
                        while (originalChar[left++] == originalChar[right--]) {
                            if (left > right ) {
                                num = j - i + 1;
                                break;
                            }
                        }
                    }
                    if (num > max) {
                        max = num;
                        num = 0;
                    }
                }
            }
        }
        System.out.println(max);
    }
}