LeetCode: Search a 2D Matrix II

LeetCode: Search a 2D Matrix II

Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties:

Integers in each row are sorted in ascending from left to right.
Integers in each column are sorted in ascending from top to bottom.

For example,

Consider the following matrix:

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[
  [1,   4,  7, 11, 15],
  [2,   5,  8, 12, 19],
  [3,   6,  9, 16, 22],
  [10, 13, 14, 17, 24],
  [18, 21, 23, 26, 30]
]

Given target = 5, return true.

Given target = 20, return false.

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public class SearchA2DMatrixII {

    public boolean searchMatrix(int[][] matrix, int target) {
        int w = matrix[0].length;

        for (int[] arr : matrix) {
            if (arr[0] <= target && arr[w - 1] >= target && (Arrays.binarySearch(arr, target) >= 0)) {
                return true;
            }
        }
        return false;
    }
}