Longest Palindromic Subsequence LeetCode solution in Java

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class Solution {
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  public int longestPalindromeSubseq(String s) {
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    StringBuilder sb = new StringBuilder(s);
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    sb.reverse();
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    String s2 = sb.toString();
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    return longestCommonSubsequence(s, s2);
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  }
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  public int longestCommonSubsequence(String text1, String text2) {
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    int[][] dp = new int[text1.length() + 1][text2.length() + 1];
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    for (int i = text1.length() - 1; i >= 0; i--) {
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      for (int j = text2.length() - 1; j >= 0; j--) {
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        char ch1 = text1.charAt(i);
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        char ch2 = text2.charAt(j);
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        if (ch1 == ch2) // diagnal
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        dp[i][j] = 1 + dp[i + 1][j + 1];
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        else // right,down considering not matchning char from s1 and skipping s2
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          // considering not matchning char from s2 and skipping s1
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          dp[i][j] = Math.max(dp[i][j + 1], dp[i + 1][j]);
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      }
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    }
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    return dp[0][0];
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  }
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}