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:

[

[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.

public class Solution { public boolean searchMatrix(int[][] matrix, int target) { int row = matrix.length; if (row == 0) return false; int col = matrix[0].length; int i = 0; int j = col - 1; while (i < row && j >= 0) { if (target < matrix[i][j]) { j--; } else if (target > matrix[i][j]) { i++; } else return true; } return false; } }

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