题解 | 公共子串计算

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 a = in.nextLine();
        String b = in.nextLine();
        String s1 = a.length() < b.length() ? a : b;
        String s2 = a.length() > b.length() ? a : b;
        if (a.length() == 0 || b.length() == 0 || a.length() == 1 && b.length() == 1 &&
                !a.equals(b)) {
            System.out.println(0);
            return;
        }
        int n = 0;
        for (int i = 0; i < s1.length(); i++) {
            for (int j = s1.length(); j > i; j--) {
                if (s2.contains(s1.substring(i, j))) {
                    n = j - i > n ? j - i : n;
                    break;
                }
            }
        }
        System.out.println(n);
    }
}