Longest Common Sub sequence

class Solution {
//Dynamic Programming O(n^2)
    public int longestCommonSubsequence(String text1, String text2) {
        int n1 = text1.length();
        int n2 = text2.length();
        if(n1 == 0 || n2 == 0)
            return 0;
        int[][] ans = new int[n2 + 1][n1 + 1];
        for(int i = 0; i < n2 + 1; i++)
            ans[i][0] = 0;
        for(int i = 0; i < n1 + 1; i++)
            ans[0][i] = 0;
        for(int i = 0; i < n2; i++)
        {
            for(int j = 0; j < n1; j++)
            {
                if(text1.charAt(j) == text2.charAt(i))
                {
                    ans[i + 1][j + 1] = ans[i][j] + 1;
                }
                else
                {
                    ans[i + 1][j + 1] = Math.max(ans[i][j + 1], ans[i + 1][j]);
                }
            }
        }
        return ans[n2][n1];
    }
    
    //Recursion O(2^n)
    public int longestCommonSubsequence(String text1, String text2, int m, int n)
    {
        if(m == 0 || n == 0)
            return 0;
        if(text1.charAt(m) == text2.charAt(n))
            return 1 + longestCommonSubsequence(text1, text2, m - 1, n - 1);
        else
            return longestCommonSubsequence(text1, text2, m, n - 1) + longestCommonSubsequence(text1, text2, m - 1, n);
    }
}