Number of Distinct Roll Sequences LeetCode solution in Java

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class Solution {
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  static long[][] dp;
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  public int distinctSequences(int n) {
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    if (n == 1) return 6;
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    int mod = 1_000_000_007;
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    dp =
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        new long[][] {
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          {0, 1, 1, 1, 1, 1},
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          {1, 0, 1, 0, 1, 0},
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          {1, 1, 0, 1, 1, 0},
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          {1, 0, 1, 0, 1, 0},
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          {1, 1, 1, 1, 0, 1},
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          {1, 0, 0, 0, 1, 0}
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        };
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    for (int i = 2; i < n; i++) {
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      long[][] temp = new long[6][6];
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      for (int j = 0; j < 6; j++) {
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        for (int k = 0; k < 6; k++) {
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          long total = 0;
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          if (dp[j][k] == 0) continue;
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          for (int l = 0; l < 6; l++) {
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            total = (total + ((l == k) ? 0 : dp[l][j])) % mod;
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          }
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          temp[j][k] = total;
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        }
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      }
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      dp = temp;
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    }
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    long result = 0;
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    for (int i = 0; i < 6; i++) {
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      for (int j = 0; j < 6; j++) {
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        result = (result + dp[i][j]) % mod;
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      }
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    }
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    return (int) (result);
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  }
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}