class Solution {
    public int longestCommonSubsequence(String text1, String text2) {

        int[][] dp = new int[text1.length()][text2.length()];

        // when 0,0
        char c_1 = text1.charAt(0);
        char c_2 = text2.charAt(0);
        if (c_1 == c_2) {
            dp[0][0] = 1;
        }else {
            dp[0][0] = 0;
        }

        // when text1 is 0
        for (int i = 1; i < text2.length() ;i++) {
            char c1 = text1.charAt(0);
            char c2 = text2.charAt(i);

            Integer result_max = Integer.MIN_VALUE;
            Integer result_1 = Integer.MIN_VALUE;
            Integer result_2 = Integer.MIN_VALUE;

            if (c1 == c2) {
                result_1 = 1;
            }
            result_2 = dp[0][i - 1];

            result_max = Math.max(result_max, result_1);
            result_max = Math.max(result_max, result_2);

            dp[0][i] = result_max;
        }
        // when text2 is 0
        for (int i = 1; i < text1.length() ;i++) {
            char c1 = text1.charAt(i);
            char c2 = text2.charAt(0);

            Integer result_max = Integer.MIN_VALUE;
            Integer result_1 = Integer.MIN_VALUE;
            Integer result_2 = Integer.MIN_VALUE;

            if (c1 == c2) {
                result_1 = 1;
            }
            result_2 = dp[i-1][0];

            result_max = Math.max(result_max, result_1);
            result_max = Math.max(result_max, result_2);

            dp[i][0] = result_max;
        }
        // go
        for (int i = 1; i < text1.length() ;i++) {
            char c1 = text1.charAt(i);
            System.out.printf("");
            for (int j = 1; j < text2.length() ;j++) {

                char c2 = text2.charAt(j);

                Integer result_max = Integer.MIN_VALUE;
                Integer result_1 = Integer.MIN_VALUE;
                Integer result_2 = Integer.MIN_VALUE;
                Integer result_3 = Integer.MIN_VALUE;
                if (c1 == c2) {
                    // option1
                    result_1 = 1 + dp[i-1][j-1];
                }

                // option2
                result_2 = dp[i-1][j];
                // option3
                result_3 = dp[i][j-1];

                result_max = Math.max(result_max, result_1);
                result_max = Math.max(result_max, result_2);
                result_max = Math.max(result_max, result_3);

                dp[i][j] = result_max;
            }
        }

        return dp[text1.length() - 1][text2.length() - 1];

        // Integer result = go(text1, text2, 0, 0);
        // return result;
    }

    Map<String, Integer> cached = new HashMap<>();
    public String get_key(int i1, int i2) {
        return i1 + "," + i2;
    }
    public Integer go(String text1, String text2, int i1, int i2) {
        if (i1 == text1.length() || i2 == text2.length()) return 0;

        String key = get_key(i1,i2);
        if (cached.containsKey(key)) {
            return cached.get(key);
        }

        char c1 = text1.charAt(i1);
        char c2 = text2.charAt(i2);

        Integer result_max = Integer.MIN_VALUE;
        Integer result_1 = Integer.MIN_VALUE;
        Integer result_2 = Integer.MIN_VALUE;
        Integer result_3 = Integer.MIN_VALUE;
        if (c1 == c2) {
            // option1
            result_1 = 1 + go(text1, text2, i1 + 1, i2 + 1);
        }

        // option2
        result_2 = go(text1, text2, i1 + 1, i2);
        // option3
        result_3 = go(text1, text2, i1, i2 + 1);

        result_max = Math.max(result_max, result_1);
        result_max = Math.max(result_max, result_2);
        result_max = Math.max(result_max, result_3);

        key = get_key(i1,i2);
        cached.put(key, result_max);

        return result_max;

    }
}