Maximum Non Negative Product in a Matrix LeetCode solution in Java

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class Solution {
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  public class Pair {
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    long min = Integer.MAX_VALUE, max = Integer.MIN_VALUE;
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    Pair() {}
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    Pair(long min, long max) {
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      this.min = min;
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      this.max = max;
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    }
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  }
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  public int maxProductPath(int[][] grid) {
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    Pair[][] dp = new Pair[grid.length][grid[0].length];
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    for (int r = grid.length - 1; r >= 0; r--) {
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      for (int c = grid[0].length - 1; c >= 0; c--) {
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        if (r == grid.length - 1 && c == grid[0].length - 1) {
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          dp[r][c] = new Pair(grid[r][c], grid[r][c]);
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        } else {
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          Pair hor = (c == grid[0].length - 1) ? new Pair() : dp[r][c + 1];
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          Pair ver = (r == grid.length - 1) ? new Pair() : dp[r + 1][c];
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          long min, max;
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          if (grid[r][c] >= 0) {
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            max = Math.max(hor.max, ver.max);
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            min = Math.min(hor.min, ver.min);
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          } else {
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            min = Math.max(hor.max, ver.max);
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            max = Math.min(hor.min, ver.min);
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          }
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          dp[r][c] = new Pair(min * grid[r][c], max * grid[r][c]);
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        }
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      }
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    }
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    int mod = (int) 1e9 + 7;
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    return dp[0][0].max < 0 ? -1 : (int) (dp[0][0].max % mod);
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  }
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}