Count Number of Texts LeetCode solution in Java

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class Solution {
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  int mod = (1000000007);
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  public int countTexts(String pressedKeys) {
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    int[] key = new int[] {0, 0, 3, 3, 3, 3, 3, 4, 3, 4};
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    int n = pressedKeys.length();
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    int[] dp = new int[n + 1];
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    dp[n] = 1;
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    for (int ind = n - 1; ind >= 0; ind--) {
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      int count = 0;
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      int num = pressedKeys.charAt(ind) - '0';
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      int rep = key[num];
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      for (int i = 0;
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          i < rep
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              && ind + i < pressedKeys.length()
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              && pressedKeys.charAt(ind) == pressedKeys.charAt(ind + i);
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          i++) {
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        count += dp[ind + i + 1];
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        count %= mod;
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      }
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      dp[ind] = count;
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    }
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    return dp[0];
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  }
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}