Knight Probability in Chessboard LeetCode solution in Java

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class Solution {
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  public double knightProbability(int n, int k, int row, int column) {
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    double[][] curr = new double[n][n];
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    double[][] next = new double[n][n];
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    curr[row][column] = 1;
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    int[][] dir = {{-2, 1}, {-1, 2}, {1, 2}, {2, 1}, {2, -1}, {1, -2}, {-1, -2}, {-2, -1}};
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    for (int p = 1; p <= k; p++) {
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      for (int i = 0; i < n; i++) {
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        for (int j = 0; j < n; j++) {
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          if (curr[i][j] != 0) {
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            for (int d = 0; d < 8; d++) {
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              int ni = i + dir[d][0];
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              int nj = j + dir[d][1];
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              if (ni < 0 || nj < 0 || ni >= n || nj >= n) {
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                continue;
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              }
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              next[ni][nj] += curr[i][j] / 8.0;
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            }
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          }
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        }
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      }
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      curr = next;
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      next = new double[n][n];
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    }
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    double sum = 0.0;
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    for (int i = 0; i < n; i++) {
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      for (int j = 0; j < n; j++) {
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        sum += curr[i][j];
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      }
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    }
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    return sum;
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  }
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}