题解 | #公共子串计算#

import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String a = scanner.next();
        String b = scanner.next();
        System.out.println(maxCommonSubstringLength(a, b));
    }
    public static int maxCommonSubstringLength(String a, String b) {
        if (a == null || b == null) {
            return 0;
        }
        int maxLength = 0;
        int aLength = a.length();
        int bLength = b.length();
        int[][] dp = new int[aLength+1][bLength+1];
        for (int i = 1; i <= aLength; ++i) {
            for (int j = 1; j <= bLength; ++j) {
                if (a.charAt(i-1) == b.charAt(j-1)) {
                    dp[i][j] = dp[i-1][j-1] + 1;
                    maxLength = Math.max(dp[i][j], maxLength);
                }
            }
        }
        return maxLength;
    }
}