Number of Paths with Max Score LeetCode solution in Java

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class Solution {
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  public int[] pathsWithMaxScore(List<String> board) {
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    int M = (int) 1e9 + 7;
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    int m = board.size();
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    int n = board.get(0).length();
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    int[][] dp = new int[m][n];
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    int[][] ways = new int[m][n];
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    ways[0][0] = 1; // base case.
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    int[][] dirs = {{-1, 0}, {0, -1}, {-1, -1}}; // all 3 ways where we can travel.
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    for (int i = 0; i < m; i++) {
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      for (int j = 0; j < n; j++) {
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        if (board.get(i).charAt(j) == 'X') {
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          continue;
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        }
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        int cur = Character.isDigit(board.get(i).charAt(j)) ? board.get(i).charAt(j) - '0' : 0;
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        for (int[] d : dirs) {
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          int x = d[0] + i;
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          int y = d[1] + j;
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          if (x < 0 || y < 0 || ways[x][y] == 0) {
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            continue;
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          }
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          if (cur + dp[x][y] > dp[i][j]) {
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            dp[i][j] = cur + dp[x][y];
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            ways[i][j] = 0;
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          }
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          if (cur + dp[x][y] == dp[i][j]) {
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            ways[i][j] += ways[x][y];
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            ways[i][j] %= M;
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          }
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        }
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      }
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    }
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    return new int[] {dp[m - 1][n - 1], ways[m - 1][n - 1]};
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  }
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}