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:

[
[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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