matrix.java

// Time Complexity : O(log(m*n))
// Space Complexity : O(1)
// Did this code successfully run on Leetcode : Yes
// Any problem you faced while coding this : No

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

        int low = 0, high = m * n - 1;

        while (low <= high) {
            int mid = low + (high - low) / 2;

            int r = mid / n;
            int c = mid % n;

            if (matrix[r][c] == target) {
                return true;
            } else if (matrix[r][c] > target) {
                high = mid - 1;
            } else {
                low = mid + 1;
            }

        }

        return false;

    }
}