编辑代码

public class Main {
    public static int longestCommonSubstring(String str1, String str2) {
        int m = str1.length();
        int n = str2.length();
        int[][] dp = new int[m + 1][n + 1];

        for (int i = 1; i <= m; i++) {
            for (int j = 1; j <= n; j++) {
                if (str1.charAt(i - 1) == str2.charAt(j - 1)) {
                    dp[i][j] = dp[i - 1][j - 1] + 1;
                } else {
                    dp[i][j] = Math.max(dp[i - 1][j], dp[i][j - 1]);
                }
            }
        }
        return dp[m][n];
    }

    public static void main(String[] args) {
        String str1 = "HHII";
        String str2 = "FFHI";
        int r = longestCommonSubstring(str1, str2);
        System.out.println("两个字符串的最大公共字符串子序列: " + r);
    }
}