题解 | #查找两个字符串a,b中的最长公共子串#

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);
        String str1 = in.nextLine();
        String str2 = in.nextLine();
        int len1 = str1.length();
        int len2 = str2.length();
        String minString = len1 < len2 ? str1 : str2;
        String maxString = len1 < len2 ? str2 : str1;
        int len = Math.min(len1, len2);
        boolean flag = true;
        for (int i = len; i >= 0; i--) {
            for (int j = 0; j + i <= len; j++) {
                String subString = minString.substring(j, j + i);
                if (maxString.contains(subString)) {
                    System.out.println(subString);
                    flag = false;
                    break;
                }
            }
            if (flag == false) break;
        }
    }
}